+ dependency on libsa works
+ set and use BINDIR/BINMODE
+ don't pull in sys/lib/lib{sa,kern}/Makefile.inc (``make clean''
doesn't make empty lib/{sa,kern} directories in each
directory/obj dir).
+ remove unnecessary targets, variables and other cruft
+ wrap lines at 80 chars
Re-ordering SRCS line in libsa/Makefile to a more logical sequence
(alphabetical by source dir) results in a libsa.a with archive members
in a different order, and a resultant bootrz that differs from the 1.3.3
bootrz. Untested as yet, so left in but commented out.
Also, _don't_ install the bootblocks (as per intent of previous commit)
or our own small libsa(!).