lib: Extract helpers for determining submission method

Couple of tests are using either determining submission method, or
pretty printing. Let's move those to helpers in lib.

v2: s/igt_show/gem_show

Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
Cc: Arkadiusz Hiler <arkadiusz.hiler@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Katarzyna Dec <katarzyna.dec@intel.com>
Cc: Petri Latvala <petri.latvala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Katarzyna Dec <katarzyna.dec@intel.com>
Acked-by: Arkadiusz Hiler <arkadiusz.hiler@intel.com>
14 files changed