edify: Remove edify_parser.

It used to be containing some unit tests for basic edify syntax, which
has been moved into recovery_component_test (commit
d770d2e7).

The edify_parser host tool supports edify built-in functions only, but
doesn't recognize the ones defined in updater. This makes it much less
useful to do any real analyzing work.

Test: mmma bootable/recovery
Change-Id: I3c12f5402d2d6698e0ef5ac6c2e7804c0fbba78a