Gate mmc0/boot0/boot1 to only be flashed by LK

- u-boot doesn't understand these names, so only flash them if we're
using LK.

Change-Id: If15b83572e22694aceccef76e72a06e1be442cd3
diff --git a/flash.sh b/flash.sh
index 1b759a2..a79e7ef 100755
--- a/flash.sh
+++ b/flash.sh
@@ -42,16 +42,17 @@
   local flash_with_uboot="$2"
 
   # Load LK if we aren't using u-boot
+  # Also, only LK can handle the mmc0* partitions.
   if [[ ${flash_with_uboot} != "true" ]]; then
     load_fastboot "${files_dir}"
-  fi
 
-  try ${FASTBOOT_CMD} erase mmc0
-  try ${FASTBOOT_CMD} erase mmc0boot0
-  try ${FASTBOOT_CMD} erase mmc0boot1
-  try ${FASTBOOT_CMD} flash mmc0 "${files_dir}/partition-table.img"
-  try ${FASTBOOT_CMD} flash mmc0boot0 "${files_dir}/bl2.img"
-  try ${FASTBOOT_CMD} flash mmc0boot1 "${files_dir}/u-boot-env.bin"
+    try ${FASTBOOT_CMD} erase mmc0
+    try ${FASTBOOT_CMD} erase mmc0boot0
+    try ${FASTBOOT_CMD} erase mmc0boot1
+    try ${FASTBOOT_CMD} flash mmc0 "${files_dir}/partition-table.img"
+    try ${FASTBOOT_CMD} flash mmc0boot0 "${files_dir}/bl2.img"
+    try ${FASTBOOT_CMD} flash mmc0boot1 "${files_dir}/u-boot-env.bin"
+  fi
   try ${FASTBOOT_CMD} flash bootloaders "${files_dir}/fip.bin"
   try ${FASTBOOT_CMD} flash boot "${files_dir}/boot_arm64.img"
   try ${FASTBOOT_CMD} flash rootfs "${files_dir}/rootfs_arm64.img"