msdkvpp: Add a huge value to inbuf pts and set mfx surface timestamp

It can be seen as a WA in the case of multi-channel transcoding (like decoder output to two channels, one for encoder and one for vpp). Normally, encoder sets min pts of a huge value to avoid negative dts, while vpp set pts without this addtional huge value, which can cause input surface pts does not fit with encoder (since both encoder and vpp accept the same buffer from decoder, means they modify the timestamp of one mfx surface). So we add this huge value to vpp to ensure enc and vpp set the same value to input mfx surface meanwhile does not break encoder's setting min pts for dts protection.