envydis: add immediates for SHFL on GM107
envydis: add immediates for SHFL on GM107

Input operands b and c can be used as immediates. When an immediate is
used for c, the field starts at bit 34 instead of 39 for the GPR.

pierremoreau/envytools,karolherbst/envytools,MoochMcGee/envytools,MoochMcGee/envytools,envytools/envytools,karolherbst/envytools,envytools/envytools,pierremoreau/envytools,karolherbst/envytools,karolherbst/envytools,MoochMcGee/envytools,grate-driver/envytools,grate-driver/envytools,hakzsam/envytools,pierremoreau/envytools,hakzsam/envytools,grate-driver/envytools,hakzsam/envytools,envytools/envytools,hakzsam/envytools,karolherbst/envytools,grate-driver/envytools,MoochMcGee/envytools,MoochMcGee/envytools,pierremoreau/envytools,hakzsam/envytools,pierremoreau/envytools,envytools/envytools,grate-driver/envytools,envytools/envytools