sconeserver/libedbus: fix missing avr32 arch exclusions

Fix missing avr32 arch exclusions regarding bluez_utils being
unavailable. Fixes:
http://autobuild.buildroot.net/results/789/78901c36517b1d897a1200ccddd79afec8a605de/



Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>