selftest/wic.py: Add test for custom bootloader config
This change just add anoher test to the wic module.
It will try to create a image with a custom bootloader
configuration. This test will use the example image
directdisk-bootloader-config to test the configfile
option for the bootloaders.
[YOCTO #8728]
(From OE-Core rev:
567cb51f15354c0398b986e32011420a5f3dd090)
Signed-off-by: Mariano Lopez <mariano.lopez@linux.intel.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>