Turn const_caller_location from a query to a hook

compiler/rustc_middle/src/mir/consts.rs

@@ -590,12 +590,12 @@ impl<'tcx> TyCtxt<'tcx> {
     pub fn span_as_caller_location(self, span: Span) -> ConstValue<'tcx> {
         let topmost = span.ctxt().outer_expn().expansion_cause().unwrap_or(span);
         let caller = self.sess.source_map().lookup_char_pos(topmost.lo());
-        self.const_caller_location((
+        self.const_caller_location(
             rustc_span::symbol::Symbol::intern(
                 &caller.file.name.for_codegen(&self.sess).to_string_lossy(),
             ),
             caller.line as u32,
             caller.col_display as u32 + 1,
-        ))
+        )
     }
 }