Revert "AMDGPU: Fold CI-specific complex SMRD patterns into existing complex patterns"

This reverts commit e065977c4b5f68ab845400b256f6a3822b1325fa.

It doesn't work. S_LOAD_DWORD_IMM_ci and friends aren't selected by any of
the patterns, so it was putting 32-bit literals into the 8-bit field.

llvm-svn: 303754