Define ro.board.first_api_level property

When a device define BOARD_SHIPPING_API_LEVEL with an API level, it
sets a vendor property ro.board.first_api_level in vendor/build.prop.
This property is initiated by vendor_init and read-only.

Bug: 176950752
Test: getprop ro.board.first_api_level
Change-Id: Ia09d2e80f1ca4a79dbe4eb0dc11b189644819cad
1 file changed