fs_mgr_overlayfs: Remove temp dir under /dev when aborting

When aborting from fs_mgr_overlayfs_mount, we should remove any temp dir
we created under /dev before aborting the program.

Bug: 306124139
Test: adb-remount-test
Change-Id: I6debf84935e39d884f2f5b3e9720fdfd4332465c