The prior auto-init implementation injected a definition of

  struct <mod>_AutoInit

into application translation units.  If the same <mod> appeared in more
than one auto-init list then the definition would be repeated and fail
to compile.  Since macro expansion cannot implement an equivalent to
include blockers we need an alternative.  Instead use functions

  <mod>_AutoInit_Construct
  <mod>_AutoInit_Destruct

to hook into module static initialization and finalization.  Function
declarations can be repeated.  Inject into an application translation
unit at most one static data instance per module.  Generate its
constructor and destructor to call the above functions for every module
in the auto-init list.

Change-Id: I202d74f8ba0a457a7688c0d22f68aacbcdc47617