VPP-127 Removed spurious use of sudo

Change-Id: I1eb18fc6379db30fb802e3b929931788f54e7dc2
Signed-off-by: Ed Warnicke <eaw@cisco.com>
diff --git a/build-root/deb/debian/vpp.preinst b/build-root/deb/debian/vpp.preinst
index f80861c..d33cacf 100644
--- a/build-root/deb/debian/vpp.preinst
+++ b/build-root/deb/debian/vpp.preinst
@@ -1,4 +1,4 @@
 #!/bin/sh -e
 
 # Add the vpp group
-sudo groupadd -f -r vpp
+groupadd -f -r vpp