a1: resolve uboot build nogit failed [1/1]

PD#SH-22449

Problem:
A1 bootloader build with --build-nogit failed

Solution:
handle BLX_IMG_NAME with --build-nogit process branch

Verify:
AD402

Change-Id: Ic2876fff9c9df8352a980e509dd389944836fa78
Signed-off-by: Yingwen Wu <yingwen.wu@amlogic.com>
1 file changed