greylist is no longer enabled by default.

greylist is needed only for application namepaces. Since we started using
linker-namesapces for vendors and other platform apps linker should not
enable greylist workaround by default.

Bug: http://b/37731053
Bug: https://issuetracker.google.com/38146125
Test: sailfish builds and boots
Test: bionic-unit-tests and linker-unit-tests pass
Change-Id: Iee83db6fb1ae754f5ade18491321d9bca3b5ead4
(cherry picked from commit e8ffe56a)