IB/ipath: Change ipath_devdata.ipath_sdma_status to be unsigned long

Andrew Morton <akpm@linux-foundation.org> pointed out that bitops
should take an unsigned long * arg.  However, the ipath driver was
doing bitops on struct ipath_devdata.ipath_sdma_status, which is u64.
Change this member to unsigned long to avoid tons of warnings when x86
fixes the bitops to take unsigned long * instead of void *.

Also, change the IPATH_SDMA_RUNNING and IPATH_SDMA_SHUTDOWN bit
numbers to 30 and 31 (instead of 62 and 63) so that we're not setting
another booby trap for someone who tries to make ipath work on a
32-bit architecture.

Signed-off-by: Roland Dreier <rolandd@cisco.com>