mount: support "-O option"; stop trying to mount swap partitions

function                                             old     new   delta
mount_main                                           975    1152    +177
umount_main                                          640     636      -4
packed_usage                                       25666   25662      -4
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(add/remove: 0/0 grow/shrink: 1/2 up/down: 177/-8)            Total: 169 bytes

4 files changed