libhardware_legacy: wifi: Add support for WIFI_EXT_MODULE.

This is needed on some devices which load SDIO module aswell as Wi-Fi
module.

Plus a trailing whitespace fix.

Forward-ported from 4b5a19601f7b8efe06bb8ee0ea0197352b479cd9

Change-Id: I3fbc0065f76d91d170fb562159ea326caa4f3345
add workaround for atk6kl wifi

Change-Id: I6dc12a6cb3e1e6063addd4974d072c36a027730a