memstick: jmb38x_ms: remove set but not used variable 'data'

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/memstick/host/jmb38x_ms.c: In function 'jmb38x_ms_issue_cmd':
drivers/memstick/host/jmb38x_ms.c:371:17: warning:
 variable 'data' set but not used [-Wunused-but-set-variable]

It's never used since introduction and can be removed.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/memstick/host/jmb38x_ms.c

@@ -368,7 +368,6 @@ static int jmb38x_ms_transfer_data(struct jmb38x_ms_host *host)
 static int jmb38x_ms_issue_cmd(struct memstick_host *msh)
 {
 	struct jmb38x_ms_host *host = memstick_priv(msh);
-	unsigned char *data;
 	unsigned int data_len, cmd, t_val;
 
 	if (!(STATUS_HAS_MEDIA & readl(host->addr + STATUS))) {
@@ -400,8 +399,6 @@ static int jmb38x_ms_issue_cmd(struct memstick_host *msh)
 			cmd |= TPC_WAIT_INT;
 	}
 
-	data = host->req->data;
-
 	if (!no_dma)
 		host->cmd_flags |= DMA_DATA;