bootscript-uboot:boot.scr.cfg: also check for bootB.cfg file
This is a fix for issue [746-001621] install-script: B Installation does notwork correctly for imx6.
On i.MX6 machines boot.cfg is renamed to bootB.cfg for installation on partition B. As a result - boot script will not be able to find this file. This commit makes boot script to check for bootB.cfg if boot.cfg was not found.
Signed-off-by: Mikhail Vanyulin mikhail.vanyulin@rtsoft.de
(cherry picked from commit 3cea1769)