(addsi3): Prefer add without carry instructions and flag input operands as commutative for condition register variant.

(addsi3): Prefer add without carry instructions and
flag input operands as commutative for condition register variant.
(subsi3): Define PowerPC patterns using subtract without carry.
(numerous): Flag input operands as commutative for condition register variant.
(mov* matchers): Use mr instruction in ! TARGET_POWERPC case as well and
mr. in condition register variant.

From-SVN: r7166