wic/utils/misc.py: Added function to search for files in canned-wks
This change add two new function to search for files in the
canned-wks folder for all the layers included in bblayers.conf.
This will be used to search for custom configuration files for
the bootloaders.
There are similar functions in the wic engine, but these are
focused in wks files only, so it was needed to create new ones.
[YOCTO #8728]
Signed-off-by: Mariano Lopez <mariano.lopez@linux.intel.com> Signed-off-by: Ross Burton <ross.burton@intel.com>
