mpeg2enc: Keep the packed data consistent with each parameters
mpeg2enc: Keep the packed data consistent with each parameters

So update paramters before packing SPS/PPS data buffers

Signed-off-by: Xiang, Haihao <8d677183e5993577d4fa73a419b76987913292d6@intel.com>

android-ia/hardware_intel_libva,CyanogenMod/android_hardware_intel_libva,halleyzhao/libva-fdo,halleyzhao/libva-fdo,android-ia/hardware_intel_libva,halleyzhao/libva-fdo,android-ia/hardware_intel_libva,CyanogenMod/android_hardware_intel_libva,CyanogenMod/android_hardware_intel_libva