Configure ObsoleteLintCustomCheck lint as fatal

Lint raises an issue ObsoleteLintCustomCheck if it detects
incompatibilities between a custom lint check jar and the lint api
itself.

This is a warning by default, but in AOSP it should be fatal.
Any custom checks are expected to run. If they don't, there is risk
of introducing bugs.

ObsoleteLintCustomCheck will now cause build breakage so that it will
be investigated immediately.

Bug: N/A
Test: TH
Change-Id: I3a46c93d5b53ee0e1add7c287af791bd1b41f1c1