scripts: deploy_chrome: run make_dev_ssd just once

This script accepts multiple partitions, so pass all of them once
rather invoking the script multiple times per partition.

BUG=b:289176310
TEST=CQ passes

Change-Id: Iab1950029c5101217a5f978007bd0d1def9b2d9c
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/4822602
Tested-by: Mike Frysinger <vapier@chromium.org>
Auto-Submit: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Jack Rosenthal <jrosenth@chromium.org>
Commit-Queue: Jack Rosenthal <jrosenth@chromium.org>
diff --git a/scripts/deploy_chrome.py b/scripts/deploy_chrome.py
index 4701481..4250c2a 100644
--- a/scripts/deploy_chrome.py
+++ b/scripts/deploy_chrome.py
@@ -234,12 +234,14 @@
         )
         # Running in VMs cause make_dev_ssd's firmware confidence checks to
         # fail. Use --force to bypass the checks.
-        cmd = (
-            "/usr/share/vboot/bin/make_dev_ssd.sh --partitions %d "
-            "--remove_rootfs_verification --force"
-        )
-        for partition in (KERNEL_A_PARTITION, KERNEL_B_PARTITION):
-            self.device.run(cmd % partition, check=False)
+        cmd = [
+            "/usr/share/vboot/bin/make_dev_ssd.sh",
+            "--partitions",
+            f"{KERNEL_A_PARTITION} {KERNEL_B_PARTITION}",
+            "--remove_rootfs_verification",
+            "--force",
+        ]
+        self.device.run(cmd, check=False)
 
         self.device.Reboot()