Write the value instead of reading it twice.

Fixes: c5c77ba1 ("staging: wilc1000: Add SDIO/SPI 802.11 driver")
Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210224163706.519658-1-marcus.folkesson@gmail.com