Require GLib 2.4 or later.

Require GLib 2.4 or later.

That means that G_GINT64_MODIFIER will be defined, so don't check
whether it's defined.

We don't use the PRI[douxX]64 macros, as we use the GLib print routines
and thus use G_GINT64_MODIFIER instead.  Get rid of the checks for
whether inttypes.h defines PRI[douxX]64; just check whether it exists at
all.

That means we don't set INTTYPES_H_DEFINES_FORMATS, so don't check for
it.

git-svn-id: http://anonsvn.wireshark.org/wireshark/trunk@25243 f5534014-38df-0310-8fa8-9805f1628bb7