syscall: return pointer from test function OrigRlimitNofile

Change-Id: I8740a2a7ebb3045d8daa97bcb0da7f31f6f7b881
Reviewed-on: https://go-review.googlesource.com/c/go/+/531996
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>

src/syscall/exec_unix_test.go

@@ -357,7 +357,7 @@ func TestRlimitRestored(t *testing.T) {
 	}
 
 	orig := syscall.OrigRlimitNofile()
-	if orig.Cur == 0 {
+	if orig == nil {
 		t.Skip("skipping test because rlimit not adjusted at startup")
 	}
 

src/syscall/export_rlimit_test.go

@@ -6,9 +6,6 @@
 
 package syscall
 
-func OrigRlimitNofile() Rlimit {
-	if rlim := origRlimitNofile.Load(); rlim != nil {
-		return *rlim
-	}
-	return Rlimit{0, 0}
+func OrigRlimitNofile() *Rlimit {
+	return origRlimitNofile.Load()
 }