* configure.ac: rename configure option `--disable-mjit` to
  `--disable-mjit-support` because `--disable-mjit` is ambiguous that
  runtime MJIT default enable option or supporting MJIT features.
  `ENABLE_MJIT` is also renamed to `MJIT_SUPPORT`

* Makefile.in: catch up this fix.

* common.mk: ditto.

* test/ruby/test_jit.rb: ditto.

* win32/Makefile.sub: catch up this fix on mswin.

* tool/mkconfig.rb: fix to pass `MJIT_SUPPORT` key.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65217 b2dd03c8-39d4-4d8f-98ff-823fe69b080e