[clang] [llvm] [NVPTX] Consolidate and cleanup various NVPTXISD nodes (NFC) (PR #145581)

[Simon Pilgrim via cfe-commits]

================
@@ -1796,27 +1769,6 @@ bool NVPTXDAGToDAGISel::tryStoreParam(SDNode *N) {
     }
     }
     break;
-  // Special case: if we have a sign-extend/zero-extend node, insert the
-  // conversion instruction first, and use that as the value operand to
-  // the selected StoreParam node.
-  case NVPTXISD::StoreParamU32: {
----------------
RKSimon wrote:

@AlexMaclean  This has removed everything but the default case (which causes MSVC build warnings) - remove the outer `switch(n->getOpcode())`?

https://github.com/llvm/llvm-project/pull/145581