Fix mrc and mrc2 with APSR_nzcv. Binutils encodes it internally as 0 where
we need it to be set to 15 for it to be equivalent to r15.

MFC after:	1 week
X-MFC with:	r275415
Sponsored by:	ABT Systems Ltd


git-svn-id: svn+ssh://svn.freebsd.org/base/head@275584 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f