Fixed building wifi modules on some systems

The hosts KERNEL_DIR/KLIB_BUILD was used during "make clean" -> EVIL!

```
....
make clean -C hardware/ti/wlan/mac80211/compat_wl12xx
make[1]: Entering directory '/hardware/ti/wlan/mac80211/compat_wl12xx'
/hardware/ti/wlan/mac80211/compat_wl12xx/config.mk:256: "WARNING: CONFIG_CFG80211_WEXT will be deactivated or not working because kernel was compiled with CONFIG_WIRELESS_EXT=n. Tools using wext interface like iwconfig will not work. To activate it build your kernel e.g. with CONFIG_LIBIPW=m."
/sbin/modprobe: invalid option -- 'l'
/sbin/modprobe: invalid option -- 'l'
make[2]: Entering directory '/usr/lib/modules/3.14.4-1-ARCH/build'
make[2]: *** No rule to make target 'clean'.  Stop.
make[2]: Leaving directory '/usr/lib/modules/3.14.4-1-ARCH/build'
Makefile:443: recipe for target 'clean' failed
make[1]: *** [clean] Error 2
make[1]: Leaving directory '/hardware/ti/wlan/mac80211/compat_wl12xx'
device/moto/jordan-common/BoardConfig.mk:210: recipe for target 'WLAN_MODULES' failed
make: *** [WLAN_MODULES] Error 2
$
````