Small fixup of the recent #include cleanup. settings.h needs button.h for HAS_BUTTON_HOLD

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@20272 a1c6a512-1295-4272-9138-f99709370657
diff --git a/apps/settings.h b/apps/settings.h
index 17d5acb..c376a46 100644
--- a/apps/settings.h
+++ b/apps/settings.h
@@ -26,6 +26,7 @@
 #include <stddef.h>
 #include "inttypes.h"
 #include "config.h"
+#include "button.h"
 #if CONFIG_CODEC == SWCODEC
 #include "audio.h"
 #endif
@@ -655,6 +656,7 @@
 #if CONFIG_CHARGING
     int backlight_timeout_plugged;
 #endif
+#ifdef HAVE_BACKLIGHT
 #ifdef HAS_BUTTON_HOLD
     int backlight_on_button_hold; /* what to do with backlight when hold
                                      switch is on */
@@ -663,6 +665,7 @@
     int lcd_sleep_after_backlight_off; /* when to put lcd to sleep after backlight
                                           has turned off */
 #endif
+#endif
 #if defined(HAVE_BACKLIGHT_FADING_INT_SETTING)
     int backlight_fade_in;  /* backlight fade in timing: 0..3 */
     int backlight_fade_out; /* backlight fade in timing: 0..7 */