Add validation for FW version in order to prevent driver initialization
in case FW version is older than expected. FW version validation is
necessary, because use of a new field 'num_of_modules' in MGPIR register
is not backward compatible. FW 'minor' and 'subminor' versions are
expected to be greater than or equal to 2000 and 1886, respectively.

Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>