drm/i915: don't report compression when fbc is disabled

When i915_fbc_status is read while fbc is disabled,
it reports compressing to be true, which is confusing.
Report compressing only when fbc is enabled.

v2 (from Paulo): commit message capitalization.

Signed-off-by: vathsala nagaraju <vathsala.nagaraju@intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474534193-9527-1-git-send-email-vathsala.nagaraju@intel.com

drivers/gpu/drm/i915/i915_debugfs.c

@@ -1658,7 +1658,8 @@ static int i915_fbc_status(struct seq_file *m, void *unused)
 		seq_printf(m, "FBC disabled: %s\n",
 			   dev_priv->fbc.no_fbc_reason);
 
-	if (INTEL_GEN(dev_priv) >= 7)
+	if (intel_fbc_is_active(dev_priv) &&
+	    INTEL_GEN(dev_priv) >= 7)
 		seq_printf(m, "Compressing: %s\n",
 			   yesno(I915_READ(FBC_STATUS2) &
 				 FBC_COMPRESSION_MASK));