cmd/compile/internal/gc: fix go.y to match y.go

In https://go-review.googlesource.com/#/c/16554/ y.go was modified
manually, but go.y (which is the source for y.go) was not changed.

Change-Id: I1273801bfd1ac65b875f4465033b0d062abff0b7
Reviewed-on: https://go-review.googlesource.com/16745Reviewed-by: Austin Clements <austin@google.com>

src/cmd/compile/internal/gc/go.y

@@ -1397,6 +1397,7 @@ xfndcl:
 		$$.Func.Nosplit = nosplit;
 		$$.Func.Noinline = noinline;
 		$$.Func.Nowritebarrier = nowritebarrier;
+		$$.Func.Nowritebarrierrec = nowritebarrierrec;
 		$$.Func.Systemstack = systemstack;
 		funcbody($$);
 	}
@@ -1588,6 +1589,7 @@ xdcl_list:
 		norace = false
 		nosplit = false
 		nowritebarrier = false
+		nowritebarrierrec = false
 		systemstack = false
 	}