_stdint.h is generated by Autotools and we don't really need it. All
supported platforms now ship with stdint.h. The only stickler was MSVC,
and since Visual Studio 2015 it also ships stdint.h now.
Original commit message from CVS:
* gst/realmedia/realhash.c:
* gst/realmedia/rtspreal.c:
Include generated "_stdint.h" instead of <stdint.h> which might not
exist on some systems.