floss: build.py missing import time

Bug: 200620285
Tag: #floss
Test: ./build.py --run-bootstrap && ./build.py

Change-Id: Ia6e8212759f87db36ef3f86a5980c2afb7661f14
diff --git a/build.py b/build.py
index 3a2f72f..3fcb2fb 100755
--- a/build.py
+++ b/build.py
@@ -34,6 +34,7 @@
 import six
 import subprocess
 import sys
+import time
 
 # Use flags required by common-mk (find -type f | grep -nE 'use[.]' {})
 COMMON_MK_USES = [