arm: zynq: Move slcr initialization to separate file

Create separate slcr driver instead of polluting common code.

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

arch/arm/mach-zynq/common.h

@@ -17,6 +17,9 @@
 #ifndef __MACH_ZYNQ_COMMON_H__
 #define __MACH_ZYNQ_COMMON_H__
 
+extern int zynq_slcr_init(void);
+
+extern void __iomem *zynq_slcr_base;
 extern void __iomem *zynq_scu_base;
 
 #endif