transmission: Fix build error "conflicting types for 'UTP_Write'" after version bump

transmission: Fix build error "conflicting types for 'UTP_Write'" after version bump

fix taken from
http://www.adminsehow.com/2012/10/how-to-install-transmission-2-71-on-debian-6-0-squeeze/

compile tested on arch sh4, fixes
http://autobuild.buildroot.org/results/638/63884de929fb7339ebf44b08cb5d1ab30010666a/

should also fix powerpc
http://autobuild.buildroot.org/results/eb4/eb486228a11a9602d4bf40e771744d2b2b40508f/

Signed-off-by: Bernd Kuhls <berndkuhls@hotmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>