Driver: Vmxnet3: Fix use of mfTableLen for big endian architectures

Signed-off-by: Shrikrishna Khare <skhare@vmware.com>
Reported-by: Masao Uebayashi <uebayasi@gmail.com>
Signed-off-by: Bhavesh Davda <bhavesh@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>