igt-dev is pretty established after a 1-year transition.

Let's end the transition and avoid confusion.

v2: Keep subjectprefix with i-g-t (Easwar)
v3: Also remove "Intel" from the line above. (Easwar)

Cc: Easwar Hariharan <easwar.hariharan@intel.com>
Cc: Petri Latvala <petri.latvala@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Easwar Hariharan <easwar.hariharan@intel.com>