Fix several instances of -Wsizeof-array-div
Fix several instances of -Wsizeof-array-div

e.g.:
 warning: expression does not compute the number of elements in this
 array; element type is '__cpu_mask' (aka 'unsigned long'), not
 'uint32_t' (aka 'unsigned int') [-Wsizeof-array-div]

for (uint i = 0; i < sizeof(mask_.__bits) / sizeof(uint32_t); ++i) {

__bits is a __cpu_mask, which is a 64-bit type. These were accessed
through uint32_t pointers so the loop bound should have been
correct. These operations can be done directly on the 64-bit type so
we can leave the array size pattern, and eliminate the casts.

The case in getNextSet should probably be rephrased in terms of
__cpu_mask to avoid the pointer casting, but this is tricker than the
other cases so I used the easy option to quiet the warning.

Change-Id: I1332584fad58439ccd9d369589519a9918e1678e

ROCm-Developer-Tools/ROCclr,ROCm-Developer-Tools/ROCclr