target-arm: Refactor CPU affinity handling

Introduces reusable definitions for CPU affinity masks/shifts and gets rid
of hardcoded magic numbers.

Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
Message-id: 7e6def4d0d91ae64615cdd2035b94d408d0a23c6.1441366248.git.p.fedin@samsung.com
[PMM: folded overlong line]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
diff --git a/target-arm/kvm32.c b/target-arm/kvm32.c
index 421ce0e..3ae57a6 100644
--- a/target-arm/kvm32.c
+++ b/target-arm/kvm32.c
@@ -181,7 +181,6 @@
     return KVM_PUT_RUNTIME_STATE;
 }
 
-#define ARM_MPIDR_HWID_BITMASK 0xFFFFFF
 #define ARM_CPU_ID_MPIDR       0, 0, 0, 5
 
 int kvm_arch_init_vcpu(CPUState *cs)
@@ -234,7 +233,7 @@
     if (ret) {
         return ret;
     }
-    cpu->mp_affinity = mpidr & ARM_MPIDR_HWID_BITMASK;
+    cpu->mp_affinity = mpidr & ARM32_AFFINITY_MASK;
 
     return kvm_arm_init_cpreg_list(cpu);
 }