This is about it on what can be disabled/deleted from libdbus
easily, back below 150K anyhow. Deeper cuts are more work than
just turning the code off as I've done here.
* dbus/dbus-marshal-basic.c (_dbus_pack_int32): we don't need the
signed int convenience funcs
* dbus/dbus-internals.c (_dbus_verbose_real): omit when not in
verbose mode
* dbus/dbus-string-util.c, dbus/dbus-string.c: more breaking
things out of libdbus
* dbus/dbus-sysdeps.c, dbus/dbus-sysdeps-util.c: same
* dbus/dbus-hash.c: purge the TWO_STRINGS crap (well, make it
tests-enabled-only, though it should probably be deleted)
* dbus/dbus-message-util.c: same stuff
* dbus/dbus-auth-util.c: same stuff
* test/unused-code-gc.py: hacky script to find code that's used
only by the bus (not libdbus) or used only by tests or not used at
all. It has some false alarms, but looks like we can clean up a
lot of size from libdbus.
* dbus/dbus-sysdeps.c, dbus/dbus-sysdeps-utils.c,
dbus/Makefile.am: initially move 10K of binary size out of libdbus
