log return value before arguments when rsync error

The arguments of rsync command seems too long. If some errors occur, it
is hard to debug. Moving return value of rsync command first could help
people at least know reason of rsync error by manuals.

fixes bug #903406

Change-Id: I1cac7bbca74824a6d47e6ceb9f654d4046fcbb9e
Merge "log return value before arguments when rsync error"