References to krb5_int16.rst and krb5_ui_2.rst were missing, but
recently began causing sphinx-build errors because Doxygen started
generating them after the stdint.h changes.
krb5_flags.rst
krb5_get_init_creds_opt.rst
krb5_gic_opt_pa_data.rst
+ krb5_int16.rst
krb5_int32.rst
krb5_kdc_rep.rst
krb5_kdc_req.rst
krb5_trace_info.rst
krb5_transited.rst
krb5_typed_data.rst
+ krb5_ui_2.rst
krb5_ui_4.rst
krb5_verify_init_creds_opt.rst
passwd_phrase_element.rst