stdint.h is for the [u]int*_t types, which is the only thing we need for
the prototypes. inttypes.h includes stdint.h and defines more thing we
don't need here.
Bump micro in case a user app was relying on this include for its own
code.
If not set, they will be defined using the channel layout setting, which
is much more convenient when using swr_alloc() instead of
swr_alloc_set_opts().
