share CodeGen::genHomeRegisterParams with XARCH-ARMARCH.

Author: shushanhf

src/coreclr/jit/codegencommon.cpp

@@ -2802,7 +2802,7 @@ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
 */
 
-#if !defined(TARGET_LOONGARCH64) && !defined(TARGET_RISCV64)
+#if !defined(TARGET_RISCV64)
 struct RegNode;
 
 struct RegNodeEdge