go-mod.bbclass: Unpack module dependency license files

go-mod.bbclass: Unpack module dependency license files

To keep the module cache logic in the go module fetchers simple, the
unpacking of the module zip files in the module cache directory is left
to the go install command in do_compile. So for do_populate_lic to find
the license files of module dependencies, do_compile needs to run before
do_populate_lic.

Signed-off-by: Christian Lindeberg <christian.lindeberg@axis.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>