drm/i915/reset: add intel_display_reset_test()

drm/i915/reset: add intel_display_reset_test()

Add a helper for checking if we want to test display reset regardless of
whether it's strictly necessary. This will come in handy in follow-up
work where we want to check this from gt reset side.

v2: Drop superfluous newline

Cc: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/487dec72f753302cd565c3a8164afa7fc1e12ed7.1741001054.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>