ARM: pmuv3: Add missing write_pmuacr()

Fix compilation on Arm by adding missing static inline write_pmuacr()
declaration.

Fixes: 0bbff9ed8165 ("perf/arm_pmuv3: Add PMUv3.9 per counter EL0 access control")
Reported-by: kernel test robot <[e-mail]>
Closes: https://lore.kernel.org/oe-kbuild-all/[e-mail]/
Signed-off-by: Rob Herring (Arm) <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Will Deacon <[e-mail]>

arch/arm/include/asm/arm_pmuv3.h

···
 	write_sysreg(val, PMUSERENR);
 }
 
+static inline void write_pmuacr(u64 val) {}
+
 static inline void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr) {}
 static inline void kvm_clr_pmu_events(u32 clr) {}
 static inline bool kvm_pmu_counter_deferred(struct perf_event_attr *attr)