(1) Makefile
  - Move DragonFly setup lines into conditional.
  - Add TEST_ENV= line for 'make test' target.

(2) files/dragonfly-default.exp
  - Have compiler environment for 'make test' target in
    this file (refered from Makefile TEST_ENV).

(3) TODO
  - Add results of 'make test' on DragonFly/i386