Drop support for GTH board

The board maintainer states:

    The GTH board is obsolete and has not been manufactured for
    several years.
    To my knowledge, no recent U-Boot build has been tested on that
    card.

So drop support for this board.

Signed-off-by: Wolfgang Denk <wd@denx.de>
Cc: Thomas Lange <thomas@corelatus.se>
Acked-by: Thomas Lange<thomas@corelatus.se>
diff --git a/arch/powerpc/cpu/mpc8xx/cpu_init.c b/arch/powerpc/cpu/mpc8xx/cpu_init.c
index eb0091b..e97ae68 100644
--- a/arch/powerpc/cpu/mpc8xx/cpu_init.c
+++ b/arch/powerpc/cpu/mpc8xx/cpu_init.c
@@ -149,8 +149,7 @@
 	 *  I owe him a free beer. - wd]
 	 */
 
-#if defined(CONFIG_GTH)	        || \
-    defined(CONFIG_HERMES)	|| \
+#if defined(CONFIG_HERMES)	|| \
     defined(CONFIG_ICU862)	|| \
     defined(CONFIG_IP860)	|| \
     defined(CONFIG_IVML24)	|| \