drm: Renaming DP training vswing pre emph defines

Adding new defines, older one will be removed in the last patch in the series.
This is to rename the defines to have levels instead of values for vswing and
pre-emph levels as the values may differ in other scenarios like low vswing of
eDP1.4 where the values are different.

Done using following cocci patch for each define:
@@
@@

 # define DP_TRAIN_VOLTAGE_SWING_400     (0 << 0)
+ # define DP_TRAIN_VOLTAGE_SWING_LEVEL_0     (0 << 0)

...
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Sonika Jindal <sonika.jindal@intel.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

include/drm/drm_dp_helper.h

@@ -191,15 +191,23 @@
 # define DP_TRAIN_VOLTAGE_SWING_SHIFT	    0
 # define DP_TRAIN_MAX_SWING_REACHED	    (1 << 2)
 # define DP_TRAIN_VOLTAGE_SWING_400	    (0 << 0)
+# define DP_TRAIN_VOLTAGE_SWING_LEVEL_0 (0 << 0)
 # define DP_TRAIN_VOLTAGE_SWING_600	    (1 << 0)
+# define DP_TRAIN_VOLTAGE_SWING_LEVEL_1 (1 << 0)
 # define DP_TRAIN_VOLTAGE_SWING_800	    (2 << 0)
+# define DP_TRAIN_VOLTAGE_SWING_LEVEL_2 (2 << 0)
 # define DP_TRAIN_VOLTAGE_SWING_1200	    (3 << 0)
+# define DP_TRAIN_VOLTAGE_SWING_LEVEL_3 (3 << 0)
 
 # define DP_TRAIN_PRE_EMPHASIS_MASK	    (3 << 3)
 # define DP_TRAIN_PRE_EMPHASIS_0	    (0 << 3)
+# define DP_TRAIN_PRE_EMPH_LEVEL_0		(0 << 3)
 # define DP_TRAIN_PRE_EMPHASIS_3_5	    (1 << 3)
+# define DP_TRAIN_PRE_EMPH_LEVEL_1		(1 << 3)
 # define DP_TRAIN_PRE_EMPHASIS_6	    (2 << 3)
+# define DP_TRAIN_PRE_EMPH_LEVEL_2		(2 << 3)
 # define DP_TRAIN_PRE_EMPHASIS_9_5	    (3 << 3)
+# define DP_TRAIN_PRE_EMPH_LEVEL_3		(3 << 3)
 
 # define DP_TRAIN_PRE_EMPHASIS_SHIFT	    3
 # define DP_TRAIN_MAX_PRE_EMPHASIS_REACHED  (1 << 5)