Remove external/tcpdump from 64-bit build blacklist.

Change-Id: I40b0c71120a5548072ecb2e552bdbd8c14283097
diff --git a/core/64_bit_blacklist.mk b/core/64_bit_blacklist.mk
index 9ae2aa5..4302c47 100644
--- a/core/64_bit_blacklist.mk
+++ b/core/64_bit_blacklist.mk
@@ -21,7 +21,6 @@
 	external/bluetooth/bluedroid \
 	external/oprofile/daemon \
 	external/oprofile/opcontrol \
-	external/tcpdump \
 	frameworks/av \
 	frameworks/base \
 	frameworks/ex \