Auto merge of #130389 - Luv-Ray:LLVMMDNodeInContext2, r=nikic

llvm: replace some deprecated functions

`LLVMMDStringInContext` and `LLVMMDNodeInContext` are deprecated, replace them with `LLVMMDStringInContext2` and `LLVMMDNodeInContext2`.
Also replace `Value` with `Metadata` in some function signatures for better consistency.

Author: bors

src/builder.rs

@@ -503,6 +503,7 @@ impl<'a, 'gcc, 'tcx> Deref for Builder<'a, 'gcc, 'tcx> {
 
 impl<'gcc, 'tcx> BackendTypes for Builder<'_, 'gcc, 'tcx> {
     type Value = <CodegenCx<'gcc, 'tcx> as BackendTypes>::Value;
+    type Metadata = <CodegenCx<'gcc, 'tcx> as BackendTypes>::Metadata;
     type Function = <CodegenCx<'gcc, 'tcx> as BackendTypes>::Function;
     type BasicBlock = <CodegenCx<'gcc, 'tcx> as BackendTypes>::BasicBlock;
     type Type = <CodegenCx<'gcc, 'tcx> as BackendTypes>::Type;

src/context.rs

@@ -414,6 +414,7 @@ impl<'gcc, 'tcx> CodegenCx<'gcc, 'tcx> {
 
 impl<'gcc, 'tcx> BackendTypes for CodegenCx<'gcc, 'tcx> {
     type Value = RValue<'gcc>;
+    type Metadata = RValue<'gcc>;
     type Function = RValue<'gcc>;
 
     type BasicBlock = Block<'gcc>;