Removed unused license code

Nothing ever reads ALL_DEPS.*.LICENSE, and its an ever-growing list
that is sorted every time, which is extremely expensive.

notice_target is never set after I4cddf9a381a1258bdc2b1b42be72c447df10d234,
remove all the related code.

Test: no change to out/build-aosp_cf_x86_64_phone.ninja
Change-Id: I0fa6a46e62ef8aa78873b43d3064b57b1c54de51