If license file md5 information (LIC_FILES_CHKSUMS variable) is
missing in the recipe then just throw a warning instead of the build
failure.
Once enough recipes' LIC_FILES_CHKSUMS are filled then this warning
will be reverted back to the the fetal error.
If LIC_FILES_CHKSUMS field is present but invalid then the it still
causes a fetal build error.
Signed-Off-By: Nitin A Kamble <nitin.a.kamble@intel.com>
