Enable local_buffer mode of cnss_diag

Bug: 37189761

Change-Id: Icfd79cecc7edd55c1ef3c2417cea64cdc3d3dfa4
Signed-off-by: Ecco Park <eccopark@google.com>
(cherry picked from commit 35620cd4918ac951efcf59fc4a3a606536a1233c)
diff --git a/init.common.diag.rc.userdebug b/init.common.diag.rc.userdebug
index e132a93..a678b81 100644
--- a/init.common.diag.rc.userdebug
+++ b/init.common.diag.rc.userdebug
@@ -107,7 +107,7 @@
 on property:persist.sys.cnss.diag_txt=false
     stop cnss_diag_txt
 
-service cnss_diag /vendor/bin/cnss_diag -q
+service cnss_diag /vendor/bin/cnss_diag -q -u
     class late_start
     user system
     group system