soc: xilinx: Create folder structure for soc specific drivers

Create directory structure with Makefile/Kconfig for adding xilinx soc
specific drivers.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>

drivers/soc/xilinx/Kconfig

@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
+menu "Xilinx SoC drivers"
+
+endmenu

drivers/soc/xilinx/Makefile

@@ -0,0 +1 @@
+# SPDX-License-Identifier: GPL-2.0