microblaze: Show u-boot banner

It is nice to see u-boot version.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/arch/microblaze/lib/board.c b/arch/microblaze/lib/board.c
index 896e73a..d22aa85 100644
--- a/arch/microblaze/lib/board.c
+++ b/arch/microblaze/lib/board.c
@@ -24,6 +24,12 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+static int display_banner(void)
+{
+	printf("\n\n%s\n\n", version_string);
+	return 0;
+}
+
 /*
  * All attempts to come up with a "common" initialization sequence
  * that works for all boards and architectures failed: some of the
@@ -45,6 +51,7 @@
 #endif
 	serial_init,
 	console_init_f,
+	display_banner,
 	interrupts_init,
 	timer_init,
 	NULL,