db845c: flash-all-aosp.sh: Format metadata when flashing

YongQin ran into an issue where adb remount was failing
because his metadata partition was old. So lets avoid
having others hit this by formatting metadata when doing
a flashall.

Signed-off-by: John Stultz <john.stultz@linaro.org>
Change-Id: I6167c45b04d73fff2b9c68181906965cf4b7d462
diff --git a/installer/db845c/flash-all-aosp.sh b/installer/db845c/flash-all-aosp.sh
index 3451998..dd6c755 100755
--- a/installer/db845c/flash-all-aosp.sh
+++ b/installer/db845c/flash-all-aosp.sh
@@ -44,5 +44,7 @@
 fastboot flash userdata "${ANDROID_PRODUCT_OUT}"/userdata.img
 echo "FLASH-ALL-AOSP: Flash vendor_boot image"
 fastboot flash vendor_boot "${ANDROID_PRODUCT_OUT}"/vendor_boot.img
+echo "FLASH-ALL-AOSP: Formatting metadata"
+fastboot format:ext4 metadata
 
 fastboot reboot