techpack: Gitignore all subdirs except stub

Gitignore all subdirs except stub under techpack.

Change-Id: Ic3e8910865aec83424b989286cc461f757d8522d
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
diff --git a/techpack/.gitignore b/techpack/.gitignore
index 58da0b8..829fdf6 100644
--- a/techpack/.gitignore
+++ b/techpack/.gitignore
@@ -1,2 +1,3 @@
 # ignore all subdirs except stub
+*
 !/stub/