faft: Use numeric sort when listing /dev/sd*

The -v option to `ls` will sort numerically:
  sda, sda1, sda2, ..., sda9, sda10, sda11
Previously, it would sort alphabetically:
  sda, sda1, sda10, sda11, sda2, ..., sda9

BUG=b:158972448, b:158015624
TEST=Run firwmare_FAFTSetup with 'mount -o ro' adjusted to something invalid

Change-Id: I8fc56bc380439df8e1f38128cc37726939344b65
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/autotest/+/2274064
Commit-Queue: Dana Goyette <dgoyette@chromium.org>
Tested-by: Dana Goyette <dgoyette@chromium.org>
Reviewed-by: Dossym Nurmukhanov <dossym@chromium.org>
diff --git a/server/cros/faft/telemetry.py b/server/cros/faft/telemetry.py
index 87b3917..2a15284 100644
--- a/server/cros/faft/telemetry.py
+++ b/server/cros/faft/telemetry.py
@@ -23,8 +23,8 @@
 
     collects the DUT-side output of :
      - `lsusb` and `lsusb -t` output to learn about the topology;
-     - `ls -l /dev/sd*` to learn which storage devices are known to the OS and
-       what partition scheme is assumed by the kernel;
+     - `ls -lv /dev/sd*` to learn which storage devices are known to the OS and
+       what partition scheme is assumed by the kernel (-v to sort numerically);
      - `fdisk -l` for the partitioning as reported in GPT/MBR
 
     Note that the return value begins with a newline.
@@ -33,7 +33,7 @@
     for cmd in [
             'lsusb',
             'lsusb -t',
-            'ls -l /dev/sd*',
+            'ls -lv /dev/sd*',
             'fdisk -l'
     ]:
         output = servo.system_output(cmd, ignore_status=True)