qlnxev: Remove now unneeded include for opt_inet.h
Since the change [1], this is not required anymore.
This change partially reverts commit 8a847947153e.
[1] 4012b63889e4 qlnxe: Let ether_ioctl() handle SIOCSIFADDR ioctl
Reviewed by: kbowling
MFC after: 5 days
Differential Revision: https://reviews.freebsd.org/D54889