ARM: zynqmp: Add platform specific arch_get_page_table

Based on the patch:
"armv8: caches: Added routine to set non cacheable region"
(sha1: dad17fd51027ad02ac8f02deed186d08109d61fd)
it is necessary to add platform specific hook.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/arch/arm/cpu/armv8/zynqmp/cpu.c b/arch/arm/cpu/armv8/zynqmp/cpu.c
index 60d7d20..f90cca3 100644
--- a/arch/arm/cpu/armv8/zynqmp/cpu.c
+++ b/arch/arm/cpu/armv8/zynqmp/cpu.c
@@ -191,4 +191,9 @@
 
 	set_sctlr(get_sctlr() | CR_C);
 }
+
+u64 *arch_get_page_table(void)
+{
+	return (u64 *)(gd->arch.tlb_addr + 0x3000);
+}
 #endif