Remove wpilib2015 from NO_BUILD_AMD64.

Change-Id: Ifa7829c81d074ea4768005c304200f2905b731ae
diff --git a/NO_BUILD_AMD64 b/NO_BUILD_AMD64
index 391b1cb..2536534 100644
--- a/NO_BUILD_AMD64
+++ b/NO_BUILD_AMD64
@@ -1,5 +1,4 @@
 -//aos/externals:wpilib
--//aos/externals:wpilib_2015
 -//third_party/allwpilib_2016/...
 -//third_party/ntcore_2016/...
 -//frc971/wpilib/...