drm/i915: Bikeshed rpm functions name a bit.

- fini goes with init, so call it intel_power_domains_fini. While
  at it shovel some of the fini code that leaked out of it back in.

- give power_enabled functions the verb _is_ to make the meaning clearer.
  Also use a __ prefix instead of _unlocked to really discourage users.

- rename runtime_pm_init/fini to enable/disable since that's what they do.

Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 622c038..5dbd5c9 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1411,7 +1411,7 @@
  *
  * Our driver uses the autosuspend delay feature, which means we'll only really
  * suspend if we stay with zero refcount for a certain amount of time. The
- * default value is currently very conservative (see intel_init_runtime_pm), but
+ * default value is currently very conservative (see intel_runtime_pm_enable), but
  * it can be changed with the standard runtime PM files from sysfs.
  *
  * The irqs_disabled variable becomes true exactly after we disable the IRQs and