Update go toolchains to versions that include syscall/zx rename

Change-Id: I277efb81c0fd02c15840b81d507ce31c76f37fae
diff --git a/linux64/go.sha1 b/linux64/go.sha1
index 0e34b1b..a1d7961 100644
--- a/linux64/go.sha1
+++ b/linux64/go.sha1
@@ -1 +1 @@
-8507575124f3c3683ddbbf71f5925b7e919f6e19
+2ad40a6eda3ac6bb3258c8a09cace23f5da8bac3
diff --git a/mac/go.sha1 b/mac/go.sha1
index 07f220a..628c044 100644
--- a/mac/go.sha1
+++ b/mac/go.sha1
@@ -1 +1 @@
-cf50801e299b4f99704cd8a2440c2e23c5b61a88
+87457403cd3dc47fb263c16b6bddf4b3bfe93a51