MIPS: Add nudges to writes for bit unlocks.

Flushing the writes lets other CPUs waiting for the lock to get it sooner.
Signed-off-by: Chad Reese <kreese@caviumnetworks.com>
Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17289/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/include/asm/bitops.h

@@ -456,6 +456,7 @@ static inline void __clear_bit_unlock(unsigned long nr, volatile unsigned long *
 {
 	smp_mb__before_llsc();
 	__clear_bit(nr, addr);
+	nudge_writes();
 }
 
 /*