1. adding locks to global device list and mr list
2. if xio_alloc failed because it could not allocate memory via ibv_reg_mr
try to allocate again via memalign

Change-Id: I55562dedf2f1a43b5d130561e19e1feeb7e4a424
Signed-off-by: Eyal Salomon <esalomon@mellanox.com>