arm: bcmbca: add bcm6846 SoC support

BCM6846 is an ARM A7 based PON Broadband SoC. It is part of the BCA
(Broadband Carrier Access origin) chipset family so it's added under
ARCH_BCMBCA platform. This initial support includes a bare-bone
implementation and dts with CPU subsystem, memory and Broadcom uart.

This SoC is supported in the linux-next git repository so the dts and
dtsi files are copied from linux with minor fix-up that needs to be
upstreamed to linux as well.

The u-boot image can be loaded from flash or network to the entry point
address in the memory and boot from there.

Signed-off-by: William Zhang <william.zhang@broadcom.com>
diff --git a/arch/arm/mach-bcmbca/Kconfig b/arch/arm/mach-bcmbca/Kconfig
index 99e26e4..891ac30 100644
--- a/arch/arm/mach-bcmbca/Kconfig
+++ b/arch/arm/mach-bcmbca/Kconfig
@@ -19,7 +19,15 @@
 	select DM_SERIAL
 	select PL01X_SERIAL
 
+config BCM6846
+	bool "Support for Broadcom 6846 Family"
+	select SYS_ARCH_TIMER
+	select CPU_V7A
+	select DM_SERIAL
+	select BCM6345_SERIAL
+
 source "arch/arm/mach-bcmbca/bcm47622/Kconfig"
 source "arch/arm/mach-bcmbca/bcm63178/Kconfig"
+source "arch/arm/mach-bcmbca/bcm6846/Kconfig"
 
 endif