soc: xilinx: zynqmp: Add soc_xilinx_zynqmp driver

soc_xilinx_zynqmp driver allows identification of family & revision
of zynqmp SoC. This driver is selected by CONFIG_SOC_XILINX_ZYNQMP.
Add this config to xilinx_zynqmp_virt_defconfig file.
Probe this driver using platdata U_BOOT_DEVICE structure which is
specified in mach-zynqmp/cpu.c.

Signed-off-by: T Karthik Reddy <t.karthik.reddy@xilinx.com>
Reviewed-by: Ashok Reddy Soma <ashok.reddy.soma@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
index 864d00a..17fb4c4 100644
--- a/drivers/soc/Kconfig
+++ b/drivers/soc/Kconfig
@@ -16,6 +16,14 @@
 	  This allows Texas Instruments Keystone 3 SoCs to identify
 	  specifics about the SoC in use.
 
+config SOC_XILINX_ZYNQMP
+	bool "Enable SoC Device ID driver for Xilinx ZynqMP"
+	depends on SOC_DEVICE && ARCH_ZYNQMP
+	help
+	  Enable this option to select SoC device id driver for Xilinx ZynqMP.
+	  This allows other drivers to verify the SoC familiy & revision
+	  using matching SoC attributes.
+
 source "drivers/soc/ti/Kconfig"
 
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