amdgcn: Convert get_global_size to clc

Signed-off-by: Jan Vesely <jan.vesely@rutgers.edu>
Reviewed-By: Aaron Watry <awatry@gmail.com>
llvm-svn: 346080
GitOrigin-RevId: 97283de27dea4ceb830fbca941d132d820b888bc
13 files changed