Merge "remount: Remove errno test & improve messaging of fs_mgr_overlayfs_mount_all" am: 7214c98d2e am: d7d2bab857 am: 0e1b203415 am: b895be9ec3

Original change: https://android-review.googlesource.com/c/platform/system/core/+/2228578

Change-Id: I31e7852d244ef97277944d60a8a86d0c708558c9
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>