buildroot

oracle-mysql: add patch to fix gcc 6.x build issue

Fixes:

 http://autobuild.buildroot.net/results/61074b69b81cd5c17a7f74dc1f7b31f3fc35fd8a/

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
(cherry picked from commit 19e78e509e5e729437d2188b28aee7655340c67d)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>