MFstable/10 r289972:

MFC r289450:

Set dev->fd to -1 when calling cam_close_spec_device with a valid dev->fd
descriptor to avoid trashing valid file descriptors that access dev->fd at a
later point in time

PR: 192671
Submitted by: Scott Ferris <scott.ferris@isilon.com>
Sponsored by: EMC / Isilon Storage Division