fmt: decrease recursion depth

This permits the test to run when using gccgo on system
without split-stack support.  See
http://gcc.gnu.org/ml/gcc-patches/2011-04/msg01420.html
http://gcc.gnu.org/PR48553

R=r
CC=golang-dev
https://golang.org/cl/4440062

src/pkg/fmt/scan_test.go

@@ -810,7 +810,9 @@ func TestScanInts(t *testing.T) {
 	})
 }
 
-const intCount = 1000
+// 800 is small enough to not overflow the stack when using gccgo on a
+// platform that does not support split stack.
+const intCount = 800
 
 func testScanInts(t *testing.T, scan func(*RecursiveInt, *bytes.Buffer) os.Error) {
 	r := new(RecursiveInt)