[PATCH v2 for-4.17 2/3] powerpc: Remove smp_mb() from arch_spin_is_locked()

Commit 51d7d5205d338 ("powerpc: Add smp_mb() to arch_spin_is_locked()") added an smp_mb() to arch_spin_is_locked(), in order to ensure that Thread 0Thread 1 spin_lock(A); spin_lock(B); r0 = spin_is_locked(B) r1 =

[PATCH v2 for-4.17 2/3] powerpc: Remove smp_mb() from arch_spin_is_locked()

Commit 51d7d5205d338 ("powerpc: Add smp_mb() to arch_spin_is_locked()") added an smp_mb() to arch_spin_is_locked(), in order to ensure that Thread 0Thread 1 spin_lock(A); spin_lock(B); r0 = spin_is_locked(B) r1 =