Mark drop calls in landing pads cold instead of noinline

Now that deferred inlining has been disabled in LLVM,
this shouldn't cause catastrophic size blowup.

compiler/rustc_codegen_gcc/src/builder.rs

@@ -1404,7 +1404,7 @@ impl<'a, 'gcc, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'gcc, 'tcx> {
         self.cx
     }
 
-    fn do_not_inline(&mut self, _llret: RValue<'gcc>) {
+    fn mark_callsite_cold(&mut self, _llret: RValue<'gcc>) {
         unimplemented!();
     }