ath10k: sdio: set skb len for all rx packets

Without this, packets larger than 1500 will silently be dropped.
Easily reproduced by sending a ping packet with a size larger
than 1500.

Co-Developed-by: Niklas Cassel <niklas.cassel@linaro.org>
Signed-off-by: Alagu Sankar <alagusankar@silex-india.com>
Signed-off-by: Niklas Cassel <niklas.cassel@linaro.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>