rsync hang in Gitian bundling step

ln5 just got his nightly build to hang in the 64 bit Linux bundling step. The reason is similar to legacy/trac#10153 (moved): libfaketime is interfering with the inner rsync workings in a bad way. Might be easiest to just copy and paste the solution that excludes rsync from libfaketime's reach. This might be safer than not having libfaketime active when running makexpi.sh.