mwifiex: fix SDIO firmware dump problem

It's been observed that firmware doesn't go back to normal
state when all firmware memories are dumped. As a result,
further commands are blocked. This happens due to missing
driver change of writing READ DONE to control register for
SDIO interface.

This patch adds a missing change to fix the problem.

Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Cathy Luo <cluo@marvell.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
diff --git a/drivers/net/wireless/mwifiex/sdio.c b/drivers/net/wireless/mwifiex/sdio.c
index f4b1de7..a3d810b8 100644
--- a/drivers/net/wireless/mwifiex/sdio.c
+++ b/drivers/net/wireless/mwifiex/sdio.c
@@ -2241,6 +2241,13 @@
 
 		if (memory_size == 0) {
 			mwifiex_dbg(adapter, DUMP, "Firmware dump Finished!\n");
+			ret = mwifiex_write_reg(adapter,
+						card->reg->fw_dump_ctrl,
+						FW_DUMP_READ_DONE);
+			if (ret) {
+				mwifiex_dbg(adapter, ERROR, "SDIO write err\n");
+				return;
+			}
 			break;
 		}