enable mdynamic-no-pic bootstrap for x86 Darwin

enable mdynamic-no-pic bootstrap for x86 Darwin

	* configure.ac (*-*-darwin*): Use mh-darwin for all Darwin variants.
	* configure: Regenerate.
	* config/mh-ppc-darwin: Rename to mh-darwin.

gcc:

	* gcc/configure.ac: Filter -mdynamic-no-pic from CFLAGS when testing for
	plugin capabilities.
	* gcc/configure: Regenerate.

gcc/testsuite:

	* lib/plugin-support.exp (plugin-test-execute): Filter -mdynamic-no-pic from
	plugin build flags on Darwin targets.

From-SVN: r166302