arm64: zynqmp: Add debug message about clearing BSS

Just have better view on system.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/arch/arm/mach-zynqmp/spl.c b/arch/arm/mach-zynqmp/spl.c
index f6f5414..f95a264 100644
--- a/arch/arm/mach-zynqmp/spl.c
+++ b/arch/arm/mach-zynqmp/spl.c
@@ -27,6 +27,7 @@
 	/* Delay is required for clocks to be propagated */
 	udelay(1000000);
 
+	debug("Clearing BSS 0x%p - 0x%p\n", __bss_start, __bss_end);
 	/* Clear the BSS */
 	memset(__bss_start, 0, __bss_end - __bss_start);