UPSTREAM: shared-qmi: Fix crash when a hotswap occurs while loading slots

(cherry picked from commit 250c09b73c68d3f6ac5263df39895e23124c8e50)

BUG=b:182827085
TEST=cros deploy dut modemmanager; restart modemmanager

Change-Id: Ib80ca6a41879727d08c37d356a73efd2f6dd8fcb
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/modemmanager-next/+/2798080
Tested-by: Pavan Holla <pholla@google.com>
Reviewed-by: Andrew Lassalle <andrewlassalle@chromium.org>
Reviewed-by: Harpreet Grewal <harpreet@chromium.org>
Reviewed-by: Eric Caruso <ejcaruso@chromium.org>
Commit-Queue: Pavan Holla <pholla@google.com>
1 file changed