Simplify

There's only one call-site for the function, so it seems fine to
inline

crates/ra_hir_def/src/nameres.rs

@@ -195,12 +195,6 @@ pub struct Resolution {
     pub import: Option<ImportId>,
 }
 
-impl Resolution {
-    fn from_macro(macro_: MacroDefId) -> Self {
-        Resolution { def: PerNs::macros(macro_), import: None }
-    }
-}
-
 #[derive(Debug, Clone)]
 struct ResolvePathResult {
     resolved_def: PerNs,

crates/ra_hir_def/src/nameres/collector.rs

@@ -182,7 +182,11 @@ where
         // In Rust, `#[macro_export]` macros are unconditionally visible at the
         // crate root, even if the parent modules is **not** visible.
         if export {
-            self.update(self.def_map.root, None, &[(name, Resolution::from_macro(macro_))]);
+            self.update(
+                self.def_map.root,
+                None,
+                &[(name, Resolution { def: PerNs::macros(macro_), import: None })],
+            );
         }
     }