use cm kernel for s4 devices only
 to do this you need this line in local_manifest
 <project name="cyanogenmod/android_kernel_htc_msm8960" path="kernel/htc/s4" remote="github" revision="cm-11.0" />
 since were slim based this allows us to use slim msm8960 kernel for m7 devices
 and cm msm8960 for ville,evita