[RFC] Patchset to compile for kernel 5.0

[rzerres]

This pathset groups the needed updates to compile the libary on targets using linux kernel 5.0

• configure.ac: Check for the availibility of a recent header of fourcc.h

  • if uapi version of the 5.0 kernel is already incorporated in the libdrm system header, DRM_FORMAT_MOD_ALLWINNER_TILED is defined. We are going to use this header
  • otherwise, we will use the kernel version of drm is is suboptimal, but the only way to make use of sunxi VE enhancements

• h.264: update code to use new structures use types.h and update dbp structure field (buf_index to timestamp)

• h.265: update code to use new structures update dbp structure field (buf_index to timestamp)

• mpeg2.c: update code to use new structures

  • incorporate mpeg2-ctrls.h
  • RFC: should we integrate mpeg2-ctrls.h in mpeg2.h instead?

• video.c: update code to use new structure drm_modifier -> DRM_FORMAT_MOD_ALLWINNER_TILEDf

[paulkocialkowski]

This is no longer required with the latest changes. Thanks!