unexport GOFLAGS

We want to explicitly pass these where we need them.

fixes #5733

License: MIT
Signed-off-by: Steven Allen <steven@stebalien.com>

mk/golang.mk

@@ -5,6 +5,7 @@ GO_MIN_VERSION = 1.11
 # pre-definitions
 GOCC ?= go
 GOTAGS ?=
+unexport GOFLAGS
 GOFLAGS ?=
 GOTFLAGS ?=