rsi: fix sdio card reset problem

card reset is not working with recent kernels. Using
host->card->ocr instead of host->ocr_avail solved the problem.

Signed-off-by: Karun Eagalapati <karun256@gmail.com>
Signed-off-by: Amitkumar Karwar <amit.karwar@redpinesignals.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>