Only mount /proc if needed, even without a rootfs
Only mount /proc if needed, even without a rootfs

Use the same code with and without a rootfs to check if mounting
/proc is necessary before doing so. If mounting it is unsuccessful
and there is no rootfs, continue as before.

Signed-off-by: David Ward <6be1308aeebeeeac115bb2fe2e0d71ae5645edd9@ll.mit.edu>
Acked-by: Serge E. Hallyn <3df611b026e4639bee8aef7a4beb2e39fcebb313@ubuntu.com>

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