[tlbuild] minor glitch in Work/libs/obsdcompat/Makefile

[Nelson H. F. Beebe]

In a build of today's snapshot (texlive-20120521), compilation failed
for Solaris 11 x86_64 because the option -Wno-pointer-sign in
Work/libs/obsdcompat/Makefile is unknown to gcc-3.x.

Although I do have a gcc-4.x compiler on this system, it generates bad
code elsewhere in the TeX Live 2012 tree, so it cannot be used.

I'm doing a manual edit to remove the offending -Wno-pointer-sign
option, and restarting.

I personally would vote for removal of all gcc-specific -Wxxx options
in TeX Live Makefiles; they too often have been compiler-version
dependent, and are of little use to end-installers (as opposed to
original code-authors) anyway.

-------------------------------------------------------------------------------
- Nelson H. F. Beebe                    Tel: +1 801 581 5254                  -
- University of Utah                    FAX: +1 801 581 4148                  -
- Department of Mathematics, 110 LCB    Internet e-mail: beebe at math.utah.edu  -
- 155 S 1400 E RM 233                       beebe at acm.org  beebe at computer.org -
- Salt Lake City, UT 84112-0090, USA    URL: http://www.math.utah.edu/~beebe/ -
-------------------------------------------------------------------------------