Does the NEC require a 20A-240V receptacle (for an air compressor) to be protected by a gfi on a temporary power pole.

No.
See 590.6 (A) Temporary Installations

"Receptacle Outlets. All 125-volt, single-phase, 15-,20-, and 30-ampere receptacle outlets that are not a part of the permanent wiring of the building or structure and that are in use by personnel shall have ground-fault circuit interrupter protection for personnel."

240 volt receptacles are exempt

If you don't provide GFCI protection you must have a Assured Equipment Grounding Conductor Program.