[x86] Rename MOVSD/STOSD/LODSD/OUTSD to MOVSL/STOSL/LODSL/OUTSL

The disassembler has a special case for 'L' vs. 'W' in its heuristic for
checking for 32-bit and 16-bit equivalents. We could expand the heuristic,
but better just to be consistent in using the 'L' suffix.

llvm-svn: 199652