IB/mthca: Use DEFINE_MUTEX() instead of mutex_init()

mthca_device_mutex() can be initialized automatically with
DEFINE_MUTEX() rather than explicitly calling mutex_init().  This
saves a bit of text and shrinks the source by a line, so we may as
well do it....

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