Another round of cleanups and maintenance

**.c:
- Cosmetic whitespace fixes.

bin/mamprobe:
- Removed. Since bin/package installs this automatically from
  src/cmd/INIT/mamprobe.sh, and there is no need for a user to invoke
  mamprobe directly, there is no need to keep a duplicate here.

bin/package, src/cmd/INIT/package.sh:
- Remove residual UWIN support (the win32 hosttype). (re: 0ea97b9)
- Don't check for presence of src/cmd/INIT; we ship this.
- Install mamprobe in $INSTALLROOT/bin (generally arch/*/bin) along
  with other similar utilities, instead of in $PACKAGEROOT/bin. No
  other changes are needed as mamake uses a PATH search to find it.

src/lib/libcmd/pathchk.c:
- Work around a bug with the MacPorts version of gcc 13.2; due to a
  problem between it and preprocessor directives in limits.h, the
  latter does not define _POSIX_NAME_MAX and _POSIX_PATH_MAX. Their
  values are fixed by POSIX so we can safely define them ourselves.

src/lib/libast/Mamfile:
- Refactor code for installing backups for missing system headers.

COPYRIGHT

@@ -16,8 +16,8 @@ ksh 93u+m general copyright notice
 #                                                                      #
 #                  Martijn Dekker <[email protected]>                   #
 #            Johnothan King <[email protected]>             #
-#         hyenias <[email protected]>          #
 #               K. Eugene Carlson <[email protected]>               #
+#         hyenias <[email protected]>          #
 #               Anuradha Weeraman <[email protected]>                #
 #                  Lev Kujawski <[email protected]>                   #
 #                      Phi <[email protected]>                      #