wlcore: drop INET dependency

Mainline build reports:

warning: (WL12XX) selects WLCORE which has unmet direct dependencies (NETDEVICES && WLAN && WL_TI && GENERIC_HARDIRQS && MAC80211 && INET)

The INET dependency was added in commit
3c6af5b5:
    wl1271_main.c:(.text+0x271052): undefined reference to `unregister_inetaddr_
notifier'
    wl1271_main.c:(.text+0x2714d7): undefined reference to `register_inetaddr_no
tifier'

    Driver is doing some filtering based on IP addresses...

but this driver no longer has that code and it builds fine even when
CONFIG_INET is not enabled, so drop that dependency and eliminate the
kconfig warning message.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Luciano Coelho <luciano.coelho@nokia.com>
Cc: John W. Linville <linville@tuxdriver.com>
Acked-by: Luciano Coelho <coelho@ti.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>