Remove additional '/' in Q_PLUGIN_EXTRA_CONF_FILES

Currently there is added an obsolote/wrong '/' when passing
Q_PLUGIN_EXTRA_CONF_FILES to the service start arguments.
Thats not a problem when using absolute paths, but wrong for
relative paths. This patch removes that extra '/'.

Change-Id: I2136d39889eaf83ecfcc711c733e95e261f455e0
Closes-Bug: #1572192
diff --git a/lib/neutron-legacy b/lib/neutron-legacy
index c2729cb..2d55abf 100644
--- a/lib/neutron-legacy
+++ b/lib/neutron-legacy
@@ -387,7 +387,7 @@
     local cfg_file
     local opts="--config-file $NEUTRON_CONF --config-file /$Q_PLUGIN_CONF_FILE"
     for cfg_file in ${Q_PLUGIN_EXTRA_CONF_FILES[@]}; do
-        opts+=" --config-file /$cfg_file"
+        opts+=" --config-file $cfg_file"
     done
     echo "$opts"
 }