Revert "Remove ping."

This reverts commit 68007028fd6a8a27ff1bee05679862ebc7dc9051

Change-Id: I07ff0d756dff12472633e535c51a29b9062cc3fc
diff --git a/target/product/base.mk b/target/product/base.mk
index 7d8c684..393f820 100644
--- a/target/product/base.mk
+++ b/target/product/base.mk
@@ -86,6 +86,7 @@
     ndc \
     netcfg \
     netd \
+    ping \
     platform.xml \
     pppd \
     pm \