`rocketboard_16`: Fix mismatched LUT sizes (#15997)

keyboards/rocketboard_16/keycode_lookup.h

@@ -26,4 +26,4 @@ typedef struct
 
 char* translate_keycode_to_string(uint16_t code);
 
-extern lookup_table_t lookup_table[366];
+extern lookup_table_t lookup_table[334];