cmd/dist: run testcshared test on linux/386

Change-Id: Iaa0fb133e5fc2078bfaf59ed721fd07a1a713ab3
Reviewed-on: https://go-review.googlesource.com/17075Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Hyang-Ah Hana Kim <hyangah@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/cmd/dist/test.go

@@ -615,9 +615,8 @@ func (t *tester) supportedBuildmode(mode string) bool {
 		}
 		return false
 	case "c-shared":
-		// TODO(hyangah): add linux-386.
 		switch pair {
-		case "linux-amd64", "darwin-amd64", "android-arm", "linux-arm", "linux-arm64":
+		case "linux-386", "linux-amd64", "darwin-amd64", "android-arm", "linux-arm", "linux-arm64":
 			return true
 		}
 		return false