ppc: Remove MPC8315ERDB 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_MPC8315 platform, remove that support as well.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/arch/powerpc/cpu/mpc83xx/hrcw/Kconfig b/arch/powerpc/cpu/mpc83xx/hrcw/Kconfig
index c657a47..75ec9c9 100644
--- a/arch/powerpc/cpu/mpc83xx/hrcw/Kconfig
+++ b/arch/powerpc/cpu/mpc83xx/hrcw/Kconfig
@@ -19,7 +19,7 @@
 	bool "1 : 2"
 
 config DDR_MC_CLOCK_MODE_1_1
-	depends on ARCH_MPC8315 || ARCH_MPC8349 || ARCH_MPC8360 || ARCH_MPC837X
+	depends on ARCH_MPC8349 || ARCH_MPC8360 || ARCH_MPC837X
 	bool "1 : 1"
 
 endchoice
@@ -143,7 +143,6 @@
 	bool "4"
 
 config CORE_PLL_VCO_DIVIDER_8
-	depends on !ARCH_MPC8315
 	bool "8"
 
 endchoice