i915/drrs/debugfs: psr status info addition

Existing debugfs entry i915_drrs_status is updated with whether PSR
is the cause for DRRS disabled state.

[v2]: Dropped the module parameter details as ctl moved from module
      parameter to debugfs. [Rodrigo]

[v3]: Crtc ID information is dropped as there is no immediate usecase.
      [Rodrigo].
Signed-off-by: NC, Ramalingam <ramalingam.c@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1511151827-6596-1-git-send-email-ramalingam.c@intel.com

drivers/gpu/drm/i915/i915_debugfs.c

@@ -3363,7 +3363,10 @@ static void drrs_status_per_crtc(struct seq_file *m,
 
 		/* disable_drrs() will make drrs->dp NULL */
 		if (!drrs->dp) {
-			seq_puts(m, "Idleness DRRS: Disabled");
+			seq_puts(m, "Idleness DRRS: Disabled\n");
+			if (dev_priv->psr.enabled)
+				seq_puts(m,
+				"\tAs PSR is enabled, DRRS is not enabled\n");
 			mutex_unlock(&drrs->mutex);
 			return;
 		}