fix(xilinx): fix comment about MEM_BASE/SIZE

Comment is not showing correct macro name that's why fix it.

Signed-off-by: Michal Simek <michal.simek@amd.com>
Change-Id: I8bc38534309285af8a27ee43782e03e9d0470267
diff --git a/plat/xilinx/zynqmp/platform.mk b/plat/xilinx/zynqmp/platform.mk
index 22eceb6..9fdc649 100644
--- a/plat/xilinx/zynqmp/platform.mk
+++ b/plat/xilinx/zynqmp/platform.mk
@@ -39,7 +39,7 @@
     $(eval $(call add_define,ZYNQMP_ATF_MEM_BASE))
 
     ifndef ZYNQMP_ATF_MEM_SIZE
-        $(error "ZYNQMP_ATF_BASE defined without ZYNQMP_ATF_SIZE")
+        $(error "ZYNQMP_ATF_MEM_BASE defined without ZYNQMP_ATF_MEM_SIZE")
     endif
     $(eval $(call add_define,ZYNQMP_ATF_MEM_SIZE))
 
@@ -56,7 +56,7 @@
     $(eval $(call add_define,ZYNQMP_BL32_MEM_BASE))
 
     ifndef ZYNQMP_BL32_MEM_SIZE
-        $(error "ZYNQMP_BL32_BASE defined without ZYNQMP_BL32_SIZE")
+        $(error "ZYNQMP_BL32_MEM_BASE defined without ZYNQMP_BL32_MEM_SIZE")
     endif
     $(eval $(call add_define,ZYNQMP_BL32_MEM_SIZE))
 endif