Stop generating unnecessary hidden API rules

The rules to extract hidden API information from an individual module
in order to create module specific files are no longer necessary as
the monolithic files are created directly from the module's class jars
and not the module specific files.

Bug: 179354495
Test: verified that the monolithic out/soong/hiddenapi/... files are
      unchanged by this change
Change-Id: I573ac17f3ea5da5a2a7e4f08718160dacca71c0c