rtl8xxxu: Do not overwrite rtl8xxxu_debug for untested chips

Fix a silly bug where the debug level was overwritten rather than
amended for untested chips.

Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
1 file changed