* ltconfig.in (with_gcc): Make the value of this option

* ltconfig.in (with_gcc):  Make the value of this option
available to the generated libtool script.
* ltmain.in (compile_command, finalize_command):  The native C
and C++ compilers on IRIX require the -LANG:std in order to to
compile correctly.   The same options should _not_ be passed
through to gcc on IRIX, or at all on other architectures for
backwards compatibility (among others).
Reported by Bob Freisenhahn <bfreisen@simple.dallas.tx.us>
Reported by Albert Chin-A-Young <china@thewrittenword.com>