configs/odroidc2: bump kernel headers to 3.14.79
following commit 7de5b0d2d83bec38ec96ef5917259d9f46df58d4, bump kernel
headers to 3.14.79 to match the kernel version.
We cannot use BR2_KERNEL_HEADERS_AS_KERNEL as some of their kernel
modifications causes glibc to fail to build.
Signed-off-by: Dagg Stompler <daggs@gmx.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>