Fix LLVM 9 IR for NVVM
Fix LLVM 9 IR for NVVM

The `immarg` suffix is sometimes appended to parameters in LLVM 9 IR,
which NVVM doesn't recognize. Simply stripping it appears to provide a
solution to this problem.

seibert/numba,cpcloud/numba,gmarkall/numba,IntelLabs/numba,stuartarchibald/numba,stonebig/numba,numba/numba,seibert/numba,sklam/numba,IntelLabs/numba,stuartarchibald/numba,sklam/numba,gmarkall/numba,IntelLabs/numba,cpcloud/numba,seibert/numba,sklam/numba,seibert/numba,cpcloud/numba,IntelLabs/numba,numba/numba,stuartarchibald/numba,stonebig/numba,numba/numba,gmarkall/numba,cpcloud/numba,stuartarchibald/numba,stonebig/numba,IntelLabs/numba,sklam/numba,cpcloud/numba,gmarkall/numba,numba/numba,numba/numba,seibert/numba,stonebig/numba,gmarkall/numba,sklam/numba,stonebig/numba,stuartarchibald/numba