UPSTREAM: mmc: mediatek: Preinitialize delay_phase in get_best_delay()

drivers/mmc/host/mtk-sd.c: In function get_best_delay:
drivers/mmc/host/mtk-sd.c:1284: warning: delay_phase.start is used uninitialized in this function
drivers/mmc/host/mtk-sd.c:1284: warning: delay_phase.maxlen is used uninitialized in this function

If delay is zero, these fields are indeed not initialized.
Let the compiler preinitialize the whole struct to fix this.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
(cherry picked from commit 62d494c)
 https://git.linaro.org/people/ulf.hansson/mmc.git next)
Signed-off-by: Wei-Ning Huang <wnhuang@google.com>

BUG=chrome-os-partner:41746
TEST=`emerge-oak chromeos-kernel-3_18`

Change-Id: I784301cbd630353248c165aba34596b4eda9b12d
Reviewed-on: https://chromium-review.googlesource.com/311980
Commit-Ready: Wei-Ning Huang <wnhuang@chromium.org>
Tested-by: Wei-Ning Huang <wnhuang@chromium.org>
Reviewed-by: Derek Basehore <dbasehore@chromium.org>

drivers/mmc/host/mtk-sd.c

@@ -1276,7 +1276,7 @@ static struct msdc_delay_phase get_best_delay(struct msdc_host *host, u32 delay)
 	int start = 0, len = 0;
 	int start_final = 0, len_final = 0;
 	u8 final_phase = 0xff;
-	struct msdc_delay_phase delay_phase;
+	struct msdc_delay_phase delay_phase = { 0, };
 
 	if (delay == 0) {
 		dev_err(host->dev, "phase error: [map:%x]\n", delay);