drm/i915: Remove i915_gem_evict_inactive()

This was only used by one external caller who would just be as happy
with evict-everything, so perform the replacement and make the function
private.

In the process we note that unbinding the inactive list should not fail,
and make it a warning instead.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index ad2a692..2fc7c55 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -3455,13 +3455,8 @@
 	}
 
 	/* Under UMS, be paranoid and evict. */
-	if (!drm_core_check_feature(dev, DRIVER_MODESET)) {
-		ret = i915_gem_evict_inactive(dev, false);
-		if (ret) {
-			mutex_unlock(&dev->struct_mutex);
-			return ret;
-		}
-	}
+	if (!drm_core_check_feature(dev, DRIVER_MODESET))
+		i915_gem_evict_everything(dev, false);
 
 	i915_gem_reset_fences(dev);