Fix some xrefs.

gnu/dist/sendmail/vacation/vacation.1

@@ -85,7 +85,7 @@ Otherwise, fatal errors, such as calling
 with incorrect arguments, or with non-existent
 .IR login s,
 are logged in the system log file, using
-syslog(8).
+syslogd(8).
 This should only be used on the command line, not in your
 .I .forward
 file.
@@ -191,7 +191,7 @@ reads the first line from the standard input for a
 UNIX
 ``From''
 line to determine the sender.
-Sendmail(8)
+sendmail(8)
 includes this
 ``From''
 line automatically.
@@ -262,7 +262,7 @@ default database file for dbm(3)
 default message to send
 .SH SEE ALSO
 sendmail(8),
-syslog(8)
+syslogd(8)
 .SH HISTORY
 The
 .B vacation