Do core interrupt masking in a less general fashion and save some instructions to decrease size and speed things up a little bit. Small fix to a few places where interrupts would get enabled again where they shouldn't have been (context switching calls when disabled).

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@16811 a1c6a512-1295-4272-9138-f99709370657

firmware/target/coldfire/system-coldfire.c

@@ -351,5 +351,5 @@ void coldfire_set_dataincontrol(unsigned long value)
     /* Have to be atomic against recording stop initiated by DMA1 */
     int level = set_irq_level(DMA_IRQ_LEVEL);
     DATAINCONTROL = (DATAINCONTROL & (1 << 9)) | value;
-    set_irq_level(level);
+    restore_irq(level);
 }