Handle vectors of 1 to 16 integers.

Change the intrinsic names to prevent the wrong one from being selected at
runtime due to the overloading.

Patch By: Michel Dänzer

Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Tom Stellard <thomas.stellard@amd.com>
llvm-svn: 174633