Slightly optimize library resolution

Even when there is only one candidate library for a particular header
we should always check if the library is already included.

Signed-off-by: Cristian Maglie <[email protected]>

Author: cmaglie

src/arduino.cc/builder/resolve_library.go

@@ -55,14 +55,14 @@ func ResolveLibrary(ctx *types.Context, header string) *types.Library {
 		return nil
 	}
 
-	if len(libraries) == 1 {
-		return libraries[0]
-	}
-
 	if markImportedLibraryContainsOneOfCandidates(markImportedLibrary, libraries) {
 		return nil
 	}
 
+	if len(libraries) == 1 {
+		return libraries[0]
+	}
+
 	reverse(libraries)
 
 	var library *types.Library