cmd/nm: do not fail TestNM if symbol has less then 3 columns in nm output

Fixes #7829

LGTM=dave
R=golang-codereviews, aram, dave
CC=golang-codereviews
https://golang.org/cl/89830043
diff --git a/src/cmd/nm/nm_test.go b/src/cmd/nm/nm_test.go
index b2320bd..829c844 100644
--- a/src/cmd/nm/nm_test.go
+++ b/src/cmd/nm/nm_test.go
@@ -19,16 +19,11 @@
 var testData uint32
 
 func checkSymbols(t *testing.T, nmoutput []byte) {
-	switch runtime.GOOS {
-	case "linux", "darwin", "solaris":
-		t.Skip("skipping test; see http://golang.org/issue/7829")
-	}
 	var checkSymbolsFound, testDataFound bool
 	scanner := bufio.NewScanner(bytes.NewBuffer(nmoutput))
 	for scanner.Scan() {
 		f := strings.Fields(scanner.Text())
 		if len(f) < 3 {
-			t.Error("nm must have at least 3 columns")
 			continue
 		}
 		switch f[2] {