RDMA/ocrdma: Remove unnecessary version.h includes

"make versioncheck" shows:

    drivers/infiniband/hw/ocrdma/ocrdma_main.c: 29 linux/version.h not needed.
    drivers/infiniband/hw/ocrdma/ocrdma_verbs.h: 31 linux/version.h not needed.

Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>