src/Makefile.b32: updates

* Rename the object object directory from 'objs' to 'BCC_obj' to be in
 sync with my previous patch for lib/Makefile.b32.

* Turn off these warnings to keep the build totally silent (with CBuilder-6
 that is).
  -w-inl    8026 Functions X are not expanded inline.
  -w-pia   8060 Possibly incorrect assignment
  -w-pin  8061 Initialization is only partially bracketed
 (same added in src/Makefile.b32)

* $(MKDIR) and $(RMDIR) have been replaced with the shell-commands 'md'
 and 'rd'. When having MingW/Msys programs 'mkdir.exe' and 'rmdir.exe' in
$PATH, this confuses Borland's make and the result (the cleaning etc.) would
 not be as expected.

* Removed the preprocessing step; no need for PP_CMD and the .int files.
 curl.exe builds fine w/o and the makefile gets simpler.

* Added a target for creating a compressed hugehelp.c if WITH_ZLIB is  defined.
It assumes groff, gzip and perl is available if such an "advanced"  users
requests it. Okay? BTW. My groff and Perl needs unix-slashes ('/').
 Other perls should handle both forms ('/' and '\').