Define `odm_available` property for hidl_interface modules.
With `odm_available: true`, the hidl_interface module installs its
vendor variant to /odm or /vendor/odm.

By putting a marker file '.hidl_for_odm' with the .hal files, the
hidl-gen will generate the Android.bp with `odm_available: true`.

Bug: 176147321
Test: build with odm_available: true for a hidl_interface module
Change-Id: I67ca08ea1ef17c277fb5d5947c568849edfa80f5