Revert my earlier const madness, we'll keep the parameter lists simple.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@16863 a1c6a512-1295-4272-9138-f99709370657
diff --git a/apps/pcmbuf.h b/apps/pcmbuf.h
index 9263285..0636245 100644
--- a/apps/pcmbuf.h
+++ b/apps/pcmbuf.h
@@ -63,7 +63,7 @@
 void pcmbuf_play_start(void);
 bool pcmbuf_crossfade_init(bool manual_skip);
 void pcmbuf_set_event_handler(void (*callback)(void));
-void pcmbuf_set_position_callback(void (*callback)(const size_t size));
+void pcmbuf_set_position_callback(void (*callback)(size_t size));
 size_t pcmbuf_free(void);
 unsigned int pcmbuf_get_latency(void);
 void pcmbuf_set_low_latency(bool state);