jemalloc: explicitly use C11

While open master can safely rely on
the std provided by the platform,
we should still explicitly set C11,
since our platform would provide an
older std.

Change-Id: I94fcdb471e0572a597b5b6601cd9b280860e6cc1
Signed-off-by: Alex Naidis <alex.naidis@linux.com>
2 files changed