driver core: firmware loader: don't cache FW_ACTION_NOHOTPLUG firmware

Generally there are only two drivers which don't need uevent to
handle firmware loading, so don't cache these firmwares during
suspend for these drivers since doing that may block firmware
loading forever.

Both the two drivers are involved in private firmware images, so
they don't hit in direct loading too.

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>