drm/i915: Introduce a for_each_intel_encoder() macro

Following the established idom, let's provide a macro to iterate through
the encoders.

spatch helps, once more, for the substitution:

  @@
  iterator name list_for_each_entry;
  iterator name for_each_intel_encoder;
  struct intel_encoder * encoder;
  struct drm_device * dev;
  @@
  -list_for_each_entry(encoder, &dev->mode_config.encoder_list, base.head) {
  +for_each_intel_encoder(dev, encoder) {
    ...
  }

I also modified a few call sites by hand where a pointer to mode_config
was directly used (to avoid overflowing 80 chars).

Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
[danvet: Wrap paramters correctly in the macro and remove spurious
space checkpatch noticed.]
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 0d7e55f..73d2308 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -171,6 +171,11 @@
 #define for_each_intel_crtc(dev, intel_crtc) \
 	list_for_each_entry(intel_crtc, &dev->mode_config.crtc_list, base.head)
 
+#define for_each_intel_encoder(dev, intel_encoder)		\
+	list_for_each_entry(intel_encoder,			\
+			    &(dev)->mode_config.encoder_list,	\
+			    base.head)
+
 #define for_each_encoder_on_crtc(dev, __crtc, intel_encoder) \
 	list_for_each_entry((intel_encoder), &(dev)->mode_config.encoder_list, base.head) \
 		if ((intel_encoder)->base.crtc == (__crtc))