KVM: selftests: Make arm64's guest_get_vcpuid() declaration arm64-only

Move the declaration of guest_get_vcpuid() to include/aarch64/processor.h,
it is implemented and used only by arm64.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

tools/testing/selftests/kvm/include/aarch64/processor.h

@@ -207,4 +207,6 @@ void smccc_hvc(uint32_t function_id, uint64_t arg0, uint64_t arg1,
 	       uint64_t arg2, uint64_t arg3, uint64_t arg4, uint64_t arg5,
 	       uint64_t arg6, struct arm_smccc_res *res);
 
+uint32_t guest_get_vcpuid(void);
+
 #endif /* SELFTEST_KVM_PROCESSOR_H */

tools/testing/selftests/kvm/include/kvm_util_base.h

@@ -707,6 +707,4 @@ kvm_userspace_memory_region_find(struct kvm_vm *vm, uint64_t start,
 
 void assert_on_unhandled_exception(struct kvm_vm *vm, uint32_t vcpuid);
 
-uint32_t guest_get_vcpuid(void);
-
 #endif /* SELFTEST_KVM_UTIL_BASE_H */