pandora: fix build

Fixes: df9251536d "libretro: satisfy vita's dynarec needs in a cleaner way"

cpu/sh2/compiler.c

@@ -1017,6 +1017,7 @@ static void rcache_unlock_all(void)
     reg_temp[i].flags &= ~HRF_LOCKED;
 }
 
+#ifdef DRC_CMP
 static u32 rcache_used_hreg_mask(void)
 {
   u32 mask = 0;
@@ -1028,6 +1029,7 @@ static u32 rcache_used_hreg_mask(void)
 
   return mask;
 }
+#endif
 
 static void rcache_clean(void)
 {

platform/gp2x/plat.c

@@ -179,6 +179,11 @@ void plat_video_menu_leave(void)
 {
 }
 
+void *plat_mem_get_for_drc(size_t size)
+{
+	return NULL;
+}
+
 void plat_early_init(void)
 {
 	// just use gettimeofday until plat_init()

platform/pandora/plat.c

@@ -442,6 +442,11 @@ void plat_wait_till_us(unsigned int us_to)
 */
 }
 
+void *plat_mem_get_for_drc(size_t size)
+{
+	return NULL;
+}
+
 void plat_early_init(void)
 {
 }