atom: Use volatile pointers for cl_khr_{global,local}_int32_{base,extended}_atomics

int64 versions were switched to volatile pointers in cl1.1
cl1.1 also renamed atom_ functions to atomic_ that use volatile pointers.
CTS and applications use volatile pointers.

Passes CTS on carrizo
no return piglit tests still pass on turks.

Reviewed-By: Aaron Watry <awatry@gmail.com>
Tested-By: Aaron Watry <awatry@gmail.com>
Signed-off-by: Jan Vesely <jan.vesely@rutgers.edu>
llvm-svn: 335280