zynq: Add support to find bootmode

Added support to find the bootmodes by reading
slcr bootmode register. this can be helpful to
autoboot the configurations w.r.t a specified bootmode.

Added this functionality on board_late_init as it's not
needed for normal initializtion part.

Signed-off-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
diff --git a/arch/arm/cpu/armv7/zynq/slcr.c b/arch/arm/cpu/armv7/zynq/slcr.c
index 717ec65..b4c11c3 100644
--- a/arch/arm/cpu/armv7/zynq/slcr.c
+++ b/arch/arm/cpu/armv7/zynq/slcr.c
@@ -101,6 +101,12 @@
 	zynq_slcr_lock();
 }
 
+u32 zynq_slcr_get_boot_mode(void)
+{
+	/* Get the bootmode register value */
+	return readl(&slcr_base->boot_mode);
+}
+
 u32 zynq_slcr_get_idcode(void)
 {
 	return (readl(&slcr_base->pss_idcode) & SLCR_IDCODE_MASK) >>