IB/ipath: Minor fix to ordering of freeing and zeroing of tid pages.

Fixed to be the same as everywhere else.  copy and then zero the page *
in the array first, and then pass the copy to the VM routines.

Signed-off-by: Dave Olson <dave.olson@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>