xtensa: xt2000: drop empty platform_init

platform_init doesn't do anything for xt2000, drop it.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

arch/xtensa/platforms/xt2000/setup.c

@@ -68,12 +68,6 @@ void __init platform_setup(char** cmdline)
 	led_print (0, "LINUX   ");
 }
 
-/* early initialization */
-
-void __init platform_init(bp_tag_t *first)
-{
-}
-
 /* Heartbeat. Let the LED blink. */
 
 void platform_heartbeat(void)