arm64: Add ARCH_BITMAIN platform

Add ARCH_BITMAIN for supporting Bitmain SoC platforms.
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>

arch/arm64/Kconfig.platforms

@@ -52,6 +52,11 @@ config ARCH_BERLIN
 	help
 	  This enables support for Marvell Berlin SoC Family
 
+config ARCH_BITMAIN
+	bool "Bitmain SoC Platforms"
+	help
+	  This enables support for the Bitmain SoC Family.
+
 config ARCH_BRCMSTB
 	bool "Broadcom Set-Top-Box SoCs"
 	select BRCMSTB_L2_IRQ