bc(1): small mdoc fixes to improve PostScript output.

The length/scale example at the beginning is not all literal.
Fix remaining "quoted" words to use .Dq
Fix a few small inline code snippets to be literal.

external/bsd/bc/dist/bc.1

@@ -1,4 +1,4 @@
-.\" $NetBSD: bc.1,v 1.2 2017/04/17 14:01:19 wiz Exp $
+.\" $NetBSD: bc.1,v 1.3 2021/01/07 19:49:13 uwe Exp $
 .\"
 .\" bc.1 - the bc manual
 .\"
@@ -109,10 +109,13 @@ The length is the
 total number of significant decimal digits in a number and the scale
 is the total number of decimal digits after the decimal point.
 For example:
-.Bd -literal
- .000001 has a length of 6 and scale of 6.
- 1935.000 has a length of 7 and a scale of 3.
-.Ed
+.Pp
+.Bl -inset -offset indent -compact
+.It Li .000001
+has a length of 6 and scale of 6.
+.It Li 1935.000
+has a length of 7 and a scale of 3.
+.El
 .Ss VARIABLES
 Numbers are stored in two types of variables, simple variables and
 arrays.
@@ -685,7 +688,9 @@ As an extension, the parenthesis are not required.
 .Ss PSEUDO STATEMENTS
 These statements are not statements in the traditional sense.
 They are not executed statements.
-Their function is performed at "compile" time.
+Their function is performed at
+.Dq compile
+time.
 .Bl -tag -width 15n
 .It Ic limits
 Print the local limits enforced by the local version of
@@ -713,7 +718,9 @@ later.
 Functions in
 .Nm
 always compute a value and return it to the caller.
-Function definitions are "dynamic" in the sense that a function is
+Function definitions are
+.Dq dynamic
+in the sense that a function is
 undefined until a definition is encountered in the input.
 That definition is then used until another
 definition function for the same name is encountered.
@@ -745,7 +752,9 @@ A runtime error will also occur for the call to an undefined function.
 .Pp
 The
 .Ar auto_list
-is an optional list of variables that are for "local" use.
+is an optional list of variables that are for
+.Dq local
+use.
 The syntax of the auto list (if present) is
 .Do Ic auto Ar name , ... ; Dc .
 (The semicolon is optional.)
@@ -908,7 +917,9 @@ The format is the same as the command line arguments.
 These arguments are processed first, so any files listed in the
 environment arguments are processed before any command line argument
 files.
-This allows the user to set up "standard" options and files to be
+This allows the user to set up
+.Dq standard
+options and files to be
 processed at every invocation of
 .Nm .
 The files in the environment variables would typically contain
@@ -1044,7 +1055,9 @@ It is not implemented in the traditional way using
 .Xr dc 1 .
 This version is a single process which parses and runs a byte code
 translation of the program.
-There is an "undocumented" option
+There is an
+.Dq undocumented
+option
 .Fl ( c )
 that causes the program to output the byte code to
 the standard output instead of running it.
@@ -1152,27 +1165,32 @@ statement on the next line.
 .It  =+ , =- , =* , =/ , =% , =^
 POSIX
 .Nm
-does not require these "old style" assignment operators to
-be defined.
-This version may allow these "old style" assignments.
+does not require these
+.Dq old style
+assignment operators to be defined.
+This version may allow these
+.Dq old style
+assignments.
 Use the
 .Ic limits
 statement to see if the installed version supports them.
-If it does support the "old style" assignment operators, the statement
-.Dq a =- 1
+If it does support the
+.Dq old style
+assignment operators, the statement
+.Dq Li a =- 1
 will decrement
-.Ar a
+.Va a
 by 1 instead of setting
-.Ar a
+.Va a
 to the value \-1.
 .It spaces in numbers
 Other implementations of
 .Nm
 allow spaces in numbers.
 For example,
-.Dq x=1 3
+.Dq Li x=1 3
 would assign the value 13 to the variable
-.Ar x .
+.Va x .
 The same statement
 would cause a syntax error in this version of
 .Nm .
@@ -1209,7 +1227,8 @@ During an interactive session, the
 signal (usually generated by the control-C character from the
 terminal) will cause execution of the current execution block to be
 interrupted.
-It will display a "runtime"
+It will display a
+.Dq runtime
 error indicating which function was interrupted.
 After all runtime structures have been cleaned up, a message will be
 printed to notify the user that
@@ -1251,7 +1270,9 @@ The limit on the number of characters in a string is
 .Dv INT_MAX
 characters.
 .It exponent
-The value of the exponent in the raise operation (^) is limited to
+The value of the exponent in the raise operation
+.Pq Ql ^
+is limited to
 .Dv LONG_MAX .
 .It variable names
 The current limit on the number of unique names is 32767 for each of