tests: use common code for scripts

This removes cut and pasted code and uses a more central source.

Signed-off-by: Ben Widawsky <benjamin.widawsky@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

tests/debugfs_reader

@@ -1,25 +1,6 @@
 #!/bin/sh
 
-if [ -d /debug/dri ] ; then
-	debugfs_path=/debug_dri
-fi
-
-if [ -d /sys/kernel/debug/dri ] ; then
-	debugfs_path=/sys/kernel/debug/dri
-fi
-
-i915_path=x
-for dir in `ls $debugfs_path` ; do
-	if [ -f $debugfs_path/$dir/i915_error_state ] ; then
-		i915_path=$debugfs_path/$dir
-		break
-	fi
-done
-
-if [ $i915_path = "x" ] ; then
-	echo i915 debugfs path not found.
-	exit 1
-fi
+. ./drm_lib.sh
 
 # read everything we can
 cat $i915_path/* > /dev/null 2>&1