IB/mthca: Get rid of might_sleep() annotations

IB/mthca: Get rid of might_sleep() annotations

The might_sleep() annotations in mthca are silly -- they all occur
shortly before calls that will end up in core functions like kmalloc()
that will print the same warning in an unsafe context anyway.  In
fact, beyond cluttering the source, we're actually bloating text with
CONFIG_DEBUG_SPINLOCK_SLEEP and/or CONFIG_PREEMPT_VOLUNTARY set.

With both options set, getting rid of the might_sleep()s saves a lot:
add/remove: 0/0 grow/shrink: 0/7 up/down: 0/-171 (-171)
function                                     old     new   delta
mthca_pd_alloc                               132     109     -23
mthca_init_cq                                969     946     -23
mthca_mr_alloc                               592     568     -24
mthca_pd_free                                 67      42     -25
mthca_free_mr                                219     194     -25
mthca_free_cq                                570     545     -25
mthca_fmr_alloc                              742     716     -26

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