libhardware_legacy/wifi: add workaround for ar6000 driver

The ar6000 driver requires the interface to be brought up in order
for scanning to function. Without this change, the supplicant fails
on first activation of wifi, and will only connect successfully
after multiple retries. This workaround is also necessary to fix
Wi-Fi hotspot mode (in conjunction with another change to
system/netd).

Backported from CM7.
Fix build error caused by ar6000 workaround

Some devices don't specify DRIVER_MODULE_NAME or DRIVER_MODULE_PATH.
Add hotspot driver loader support

Change-Id: I1489b7291595a41fea4722f14c7d5937df3208f8

Conflicts:
	wifi/Android.mk