ath10k: sdio: disable fwlog prints

The SDIO firmware may turn it on based on scratch registers so disable the
firmware log to avoid that.

Co-developed-by: Wen Gong <wgong@codeaurora.org>
Signed-off-by: Alagu Sankar <alagusankar@silex-india.com>
Signed-off-by: Wen Gong <wgong@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>