ath10k: re-enable the firmware fallback mechanism for testmode

The ath10k testmode uses request_firmware_direct() in order to avoid
producing firmware load warnings. Disabling the fallback mechanism was a
side effect of disabling warnings.

We now have a new API that allows us to avoid warnings while keeping the
fallback mechanism enabled. So use that instead.

Signed-off-by: Andres Rodriguez <andresx7@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>