Changes from v5:
2/3 arm: pmu: Check cycle count increases
* Use universal initializer {0} despite spurious compiler warnings.
* Add Drew's Reviewed-by.3/3 arm: pmu: Add CPI checking * Use numeric constant 0 directly with no intermediate variable. * More tabs in inline assembly. * Make A32/A64 inline assembly justification comments uniform. * Check argc properly. Thanks, Christopher Covington
