MIPS: Remove redundant instructions from arch_spin_{,try}lock.

We were doing:
   SRL  $r,$?,16
   ANDI $r,$r,0xffff

The logical right shift by 16 leaves the upper 16 bits clear, so the
subsequent masking out of those bits is redundant, and can safely be
removed.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/include/asm/spinlock.h

@@ -71,7 +71,6 @@ static inline void arch_spin_lock(arch_spinlock_t *lock)
 		"	 nop						\n"
 		"	srl	%[my_ticket], %[ticket], 16		\n"
 		"	andi	%[ticket], %[ticket], 0xffff		\n"
-		"	andi	%[my_ticket], %[my_ticket], 0xffff	\n"
 		"	bne	%[ticket], %[my_ticket], 4f		\n"
 		"	 subu	%[ticket], %[my_ticket], %[ticket]	\n"
 		"2:							\n"
@@ -105,7 +104,6 @@ static inline void arch_spin_lock(arch_spinlock_t *lock)
 		"	beqz	%[my_ticket], 1b			\n"
 		"	 srl	%[my_ticket], %[ticket], 16		\n"
 		"	andi	%[ticket], %[ticket], 0xffff		\n"
-		"	andi	%[my_ticket], %[my_ticket], 0xffff	\n"
 		"	bne	%[ticket], %[my_ticket], 4f		\n"
 		"	 subu	%[ticket], %[my_ticket], %[ticket]	\n"
 		"2:							\n"
@@ -153,7 +151,6 @@ static inline unsigned int arch_spin_trylock(arch_spinlock_t *lock)
 		"							\n"
 		"1:	ll	%[ticket], %[ticket_ptr]		\n"
 		"	srl	%[my_ticket], %[ticket], 16		\n"
-		"	andi	%[my_ticket], %[my_ticket], 0xffff	\n"
 		"	andi	%[now_serving], %[ticket], 0xffff	\n"
 		"	bne	%[my_ticket], %[now_serving], 3f	\n"
 		"	 addu	%[ticket], %[ticket], %[inc]		\n"
@@ -178,7 +175,6 @@ static inline unsigned int arch_spin_trylock(arch_spinlock_t *lock)
 		"							\n"
 		"1:	ll	%[ticket], %[ticket_ptr]		\n"
 		"	srl	%[my_ticket], %[ticket], 16		\n"
-		"	andi	%[my_ticket], %[my_ticket], 0xffff	\n"
 		"	andi	%[now_serving], %[ticket], 0xffff	\n"
 		"	bne	%[my_ticket], %[now_serving], 3f	\n"
 		"	 addu	%[ticket], %[ticket], %[inc]		\n"