Fix unused variable/function warnings

Author: dos1

src/opengl/extensions.c

@@ -167,14 +167,6 @@ static uint32_t _al_ogl_version(void)
 
 
 
-static bool _al_ogl_version_3_only(int flags)
-{
-   const int mask = ALLEGRO_OPENGL_3_0 | ALLEGRO_OPENGL_FORWARD_COMPATIBLE;
-   return (flags & mask) == mask;
-}
-
-
-
 /* print_extensions:
  * Given a string containing extensions (i.e. a NULL terminated string where
  * each extension are separated by a space and which names do not contain any

src/sdl/sdl_keyboard.c

@@ -379,6 +379,7 @@ static ALLEGRO_KEYBOARD *sdl_get_keyboard(void)
 
 static bool sdl_set_keyboard_leds(int leds)
 {
+   (void)leds;
    return false;
 }
 

src/sdl/sdl_system.c

@@ -21,6 +21,7 @@ ALLEGRO_DEBUG_CHANNEL("SDL")
 
 static ALLEGRO_SYSTEM_INTERFACE *vt;
 
+#ifdef DEBUGMODE
 #define _E(x) if (type == x) return #x;
 static char const *event_name(int type)
 {
@@ -68,6 +69,7 @@ static char const *event_name(int type)
    return "(unknown)";
 }
 #undef _E
+#endif
 
 static void sdl_heartbeat(void)
 {