Request format macros from inttypes.h explicitly.

This helps ensure the availability of PRI* macros from .pac files,
which cannot create this definition themselves since the inclusion
of binpac.h is hardcoded to be placed very early in the generated
code and already includes inttypes.h itself.
Merge remote-tracking branch 'origin/topic/jsiwek/snmp'

* origin/topic/jsiwek/snmp:
  Request format macros from inttypes.h explicitly.