AMDGPU/GlobalISel: Fix assert on multi-return side effect intrinsics
AMDGPU/GlobalISel: Fix assert on multi-return side effect intrinsics

llvm.amdgcn.else hits this.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@371812 91177308-0d34-0410-b5e6-96231b3b80d8

GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm