Add AOSP support for Lynx

We will have a 'vendor' project containing proprietary blobs
to be able to build and flash Pixel device when vendor source is not
available.
The project name is
platform/vendor/aosp/google_devices/lynx

and the path is
vendor/google_devices/lynx

TEST:make

BUG: 240203789
Change-Id: I33af4dce2b60f5de21d8998e445d2f8abd2b7e01