MIPS: add initial infrastructure for Broadcom MIPS SoCs

CFE checks CPU Thread in a different way (using register $22):
mfc0	t1, C0_BCM_CONFIG, 3 # $22
li	t2, CP0_CMT_TPID # (1 << 31)
and	t1, t2
bnez	t1, 2f	# if we are running on thread 1, skip init
nop

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index d97930e..c97ea41 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -75,6 +75,15 @@
 	select OF_CONTROL
 	select DM
 
+config ARCH_BMIPS
+	bool "Support BMIPS SoCs"
+	select OF_CONTROL
+	select DM
+	select CLK
+	select CPU
+	select RAM
+	select SYSRESET
+
 config MACH_PIC32
 	bool "Support Microchip PIC32"
 	select OF_CONTROL
@@ -123,6 +132,7 @@
 source "board/pb1x00/Kconfig"
 source "board/qemu-mips/Kconfig"
 source "arch/mips/mach-ath79/Kconfig"
+source "arch/mips/mach-bmips/Kconfig"
 source "arch/mips/mach-pic32/Kconfig"
 
 if MIPS