* configure.ac: Use here-documents to generate cpuopts.tmp.
Various fixes and changes to argument processing.
Reflect changes to librpc Makefile.ams.
* acinclude.m4: Use here-documents to generate cpuopts.tmp.
* aclocal/check-itron.m4: Remove HAS_IRON_API.
* aclocal/check-multiprocessing.m4: Remove HAS_MP.
* aclocal/check-posix.m4: Remove HAS_POSIX_API.