Merge non-SDK @removed API and light greylist

@removed APIs are not part of the public SDK but we do not want
to block access to them. Use the recently added removed-dex.txt
list of @removed API signatures and merge it into the hidden API
light greylist programmatically.

Note that due to Doclava's rule precedence, @removed APIs which
override a public SDK method are considered public and are
whitelisted. We have to intersect removed-dex.txt with private-dex.txt
to satisfy the rule that light greylist is a subset of private-dex.txt.

Bug: 78182899
Test: make out/target/common/obj/PACKAGING/removed-dex.txt
Change-Id: I44e54c405fc667d54a990b9ded1de8456802545e