update boehm-gc for powerpc m64 darwin.

boehm-gc:

	* powerpc_darwin_mach_dep.s:  Update for m64.  Add eh frames.
	Do not build or use the picsymbol stub for Darwin >= 9.
	* tests/test.c (reverse_test):  Modify count for ppc64-darwin.
	* pthread_support.c (GC_get_thread_stack_base): Correct a debug
	statement.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@167681 138bc75d-0d04-0410-961f-82ee72b054a4