i.MX31: Now that it matters because there's a debug screeen that allows changing things while running, some DVFS/DPTC stuff has to be done more carefully. Trim out some stuff and group functions better as well.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@29122 a1c6a512-1295-4272-9138-f99709370657

firmware/target/arm/imx31/gigabeat-s/power-gigabeat-s.c

@@ -129,7 +129,8 @@ bool tuner_powered(void)
 void power_off(void)
 {
     /* Turn off voltage and frequency scaling */
-    dvfs_dptc_stop();
+    dvfs_stop();
+    dptc_stop();
 
     /* Cut backlight */
     _backlight_off();