Pull yesno_pop out of the radio code as it is a nice simple resuasble yesno api worth reusing

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@30183 a1c6a512-1295-4272-9138-f99709370657

apps/radio/presets.c

@@ -59,8 +59,6 @@ static char filepreset[MAX_PATH]; /* preset filename variable */
 
 static int num_presets = 0; /* The number of presets in the preset list */
 
-bool yesno_pop(const char* text); /* radio.c */
-
 int radio_current_preset(void)
 {
     return curr_preset;