powerpc/64s: Avoid a branch for ppc_msgsnd

IPIs are a pretty hot path and we already have the ability to do asm feature
patching, so use it.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Change log detail]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Nicholas Piggin 2017-04-13 20:16:23 +10:00 • committed by Michael Ellerman
commit a5adf28246