Fix the missing dpi_tbl_lock mutex initialization.

Fixes: 0ac20faf ("RDMA/bnxt_re: Reorg the bar mapping")
Link: https://lore.kernel.org/r/1691642677-21369-4-git-send-email-selvin.xavier@broadcom.comSigned-off-by: Kashyap Desai <kashyap.desai@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>