drm/i915: Rename IS_GEN to IS_GEN_RANGE

RANGE makes it longer, but clearer. We are also going to add a macro to
check an individual gen, so add the _RANGE prefix here.

Diff generated with:

sed 's/IS_GEN(/IS_GEN_RANGE(/g' drivers/gpu/drm/i915/{*/,}*.{c,h} -i

v2: use IS_GEN rather than GT_GEN

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181212181044.15886-1-lucas.demarchi@intel.com

drivers/gpu/drm/i915/intel_fbc.c

@@ -787,7 +787,7 @@ static bool intel_fbc_can_activate(struct intel_crtc *crtc)
 	 * having a Y offset that isn't divisible by 4 causes FIFO underrun
 	 * and screen flicker.
 	 */
-	if (IS_GEN(dev_priv, 9, 10) &&
+	if (IS_GEN_RANGE(dev_priv, 9, 10) &&
 	    (fbc->state_cache.plane.adjusted_y & 3)) {
 		fbc->no_fbc_reason = "plane Y offset is misaligned";
 		return false;