bcm968580xref: add initial support

This add the initial support of the broadcom reference
board bcm968580xref with a bcm6858 SoC.

This board has 512 MB of ram, 256 MB of flash (nand),
2 usb port, 1 uart, 4 ethernet ports (LAN), 1 ethernet port (WAN).

Signed-off-by: Philippe Reynes <philippe.reynes@softathome.com>
diff --git a/board/broadcom/bcm968580xref/Kconfig b/board/broadcom/bcm968580xref/Kconfig
new file mode 100644
index 0000000..b573036
--- /dev/null
+++ b/board/broadcom/bcm968580xref/Kconfig
@@ -0,0 +1,17 @@
+if ARCH_BCM6858
+
+config SYS_VENDOR
+	default "broadcom"
+
+config SYS_BOARD
+	default "bcm968580xref"
+
+config SYS_CONFIG_NAME
+	default "broadcom_bcm968580xref"
+
+endif
+
+config TARGET_BCM968580XREF
+	bool "Support Broadcom bcm968580xref"
+	depends on ARCH_BCM6858
+	select ARM64