core: Separate ARM CPU detection from initialisation

This separate the ARM CPU feature detection code from the initialisation
so that we can reuse it in tests, like we did for x86 a while back.

src/pulsecore/cpu-arm.h

@@ -35,6 +35,7 @@ typedef enum pa_cpu_arm_flag {
     PA_CPU_ARM_VFPV3    = (1 << 5)
 } pa_cpu_arm_flag_t;
 
+void pa_cpu_get_arm_flags(pa_cpu_arm_flag_t *flags);
 pa_bool_t pa_cpu_init_arm(pa_cpu_arm_flag_t *flags);
 
 /* some optimized functions */