surfaceflinger: Add ifdefs for secure display query

 * The HWC_SECURE feature is only implemented for devices using
   QC-CAF hwcomposers.

Change-Id: I1aa72864ba6a0e62fd7cee74631b57200db3db4f
Merge branch 'cm-12.0' of git://github.com/CyanogenMod/android_frameworks_native into cm-12.0