sdl/render: give names to Texture.Query()'s returned parameters
sdl/render: give names to Texture.Query()'s returned parameters

This was done to let users know what the returned parameters when they
are using `go doc` (e.g. `go doc sdl.Texture.Query`).

Signed-off-by: Lilis Iskandar <f9acb790f2c75b127492316321ece0121b8eed9b@veand.co>

veandco/go-sdl2,veandco/go-sdl2