ft-channel: clean up some debug messages
ft-channel: clean up some debug messages

DEBUG uses macros to prepend the function name, so it's not necessary
to do it yourself.

I'm unconvinced all these are necessary too, but oh well.

Signed-off-by: Jonny Lamb <3d1fb3642aaab2ff70e3392a5ab916bf99eed6a3@collabora.co.uk>

Distrotech/telepathy-glib,Distrotech/telepathy-glib,Distrotech/telepathy-glib,Distrotech/telepathy-glib,Distrotech/telepathy-glib