linux-imx

selftests: firmware: only modprobe if driver is missing

No need to load test_firmware if its already there.
Also use a more generic form to recommend what is required
to be built.

Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>