This gives us better diagnostic messages on failure, particularly for
BIND_MOUNT_ERROR_FIND_DEST_MOUNT where we previously said "Invalid
argument".
Signed-off-by: Simon McVittie <smcv@collabora.com>
It's shorter and more reliable. Also GCC/CLang specific, but that's
fine because that's all we support anyways.
Closes: #69Closes: #70
Approved by: mrunalp