IB/core: Fix unaligned accesses

Addresses the following kernel logs seen during boot of sparc systems:

Kernel unaligned access at TPC[103bce50] cm_find_listen+0x34/0xf8 [ib_cm]
Kernel unaligned access at TPC[103bce50] cm_find_listen+0x34/0xf8 [ib_cm]
Kernel unaligned access at TPC[103bce50] cm_find_listen+0x34/0xf8 [ib_cm]
Kernel unaligned access at TPC[103bce50] cm_find_listen+0x34/0xf8 [ib_cm]
Kernel unaligned access at TPC[103bce50] cm_find_listen+0x34/0xf8 [ib_cm]

Signed-off-by: David Ahern <david.ahern@oracle.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>