opengl: Regenerate GPU emulation encoder sources.

opengl: Regenerate GPU emulation encoder sources.

This patch updates the encoder sources to match the auto-generated
output of the latest 'emugen' tools from sdk/emulator/opengl/

Generated by using external/qemu/distrib/update-emugl-source.sh

This shall only results in minor changes:

  - Minor indentation fixes.
  - Using 'const' to define constant tables.
  - Using anonymous namespaces in the encoders.

Change-Id: Ib282b31c4c05da897157ef90e5a9deb914a08bda