libmix: the frame ordering issue for AVC
libmix: the frame ordering issue for AVC

BZ: 3255

POC should be integer.
Each time IDR arrives, set the NextFramePOC to be nagative, didn't force the IDR to be outputed.
should't force the frame output when mfirstFlag is set.

Change-Id: I75281aafa148c88f0de58981969e1c43ea8d2684
Signed-off-by: ywan171 <a894e14e13288e1a29dcb1fe659df3df28bf27d7@intel.com>

SlimRoms/hardware_intel_common_libva,SlimRoms/hardware_intel_common_libva,OneRom/hardware_intel_common_libva,DirtyUnicorns/android_hardware_intel_common_libva,CyanogenMod/android_hardware_intel_common_libva,CyanogenMod/android_hardware_intel_common_libva,geekboxzone/mmallow_hardware_intel_common_libva,geekboxzone/mmallow_hardware_intel_common_libva,CyanogenMod/android_hardware_intel_common_libva,CM-zenfone2/android_hardware_intel_common_libva,CM-zenfone2/android_hardware_intel_common_libva,DirtyUnicorns/android_hardware_intel_common_libva,CM-zenfone2/android_hardware_intel_common_libva,SlimRoms/hardware_intel_common_libva,OneRom/hardware_intel_common_libva,DirtyUnicorns/android_hardware_intel_common_libva,geekboxzone/mmallow_hardware_intel_common_libva,OneRom/hardware_intel_common_libva