Unhandled marginal case produced a warning in Clang static analyzer. Change-Id: I3e2fc4182fa4f863acfb972b1e7a512fce5bf33a Signed-off-by: Tomas Vanek <vanekt@fbl.cz> Suggested-by: Matthias Welwarsky <matthias@welwarsky.de> Reviewed-on: http://openocd.zylin.com/4357 Tested-by: jenkins Reviewed-by: Matthias Welwarsky <matthias@welwarsky.de>