Don't use ISO C++11 constructs in code when building in C++98 mode

The added = doesn't hurt, and fixes building with clang 3.4.

Change-Id: Ic4298239134c0f9659ec86efe155401e2f9a0f3e
Signed-off-by: Bernhard Rosenkränzer <Bernhard.Rosenkranzer@linaro.org>