ppc: Remove T4160RDB board

This board has not been converted to CONFIG_DM_PCI by the deadline and is
also missing conversion to CONFIG_DM.  Remove it.  As this is the last
ARCH_T4160 platform, remove that support as well.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/arch/powerpc/cpu/mpc85xx/speed.c b/arch/powerpc/cpu/mpc85xx/speed.c
index e6e3f17..e229a5c 100644
--- a/arch/powerpc/cpu/mpc85xx/speed.c
+++ b/arch/powerpc/cpu/mpc85xx/speed.c
@@ -126,8 +126,7 @@
 	 * it uses 6.
 	 * T2080 rev 1.1 and later also use half mem_pll comparing with rev 1.0
 	 */
-#if defined(CONFIG_ARCH_T4240) || defined(CONFIG_ARCH_T4160) || \
-	defined(CONFIG_ARCH_T2080)
+#if defined(CONFIG_ARCH_T4240) || defined(CONFIG_ARCH_T2080)
 	svr = get_svr();
 	switch (SVR_SOC_VER(svr)) {
 	case SVR_T4240: