Add symbol_inject to Soong prebuilts.

Bug: 208481704
Test: None
Change-Id: I40ff59d5096e989ae39307dabc7f4d96f53164d0
diff --git a/build-prebuilts.sh b/build-prebuilts.sh
index 5550c51..4df0a47 100755
--- a/build-prebuilts.sh
+++ b/build-prebuilts.sh
@@ -106,6 +106,7 @@
         py3-launcher-autorun64
         runextractor
         soong_zip
+        symbol_inject
         toybox
         xz
         zip2zip