Tweak toolchain path, add vendor/quantenna/drivers

To switch to a quantenna 4.7.0 based kernel from the v37.4.2.89 SDK,
we need to switch over to the 4.8.5 toolchain, which uses a different
path.

Add the vendor/quantenna/drivers standalone package to the image, that
package contains the binary kernel modules from the v37.4.2.89 SDK.

Change-Id: I8d4fe3974c532c350f338e63fbef12ff0bb18b25
1 file changed