fs_mgr: fix errno setted by mount_with_alternatives

mount_with_alternatives should set errno to match the 1st mount failure.

Bug: N/A
Test: run `fs_mgr -a <fake_fstab>` and check dmesg log
Change-Id: If4148d327f75c659b843e95f85568ea49c5d0180
Signed-off-by: NIEJuhu <niejuhu@xiaomi.com>
1 file changed