fix a typo: taget_env -> target_env

This typo was introduced in https://github.com/rust-lang/rust/pull/47334.
A couple tests bitrotted as a result, so we fix those too, and move them
to a more sensible place.

src/libstd/sys/unix/net.rs

@@ -395,30 +395,3 @@ fn on_resolver_failure() {
 
 #[cfg(not(target_env = "gnu"))]
 fn on_resolver_failure() {}
-
-#[cfg(all(test, taget_env = "gnu"))]
-mod test {
-    use super::*;
-
-    #[test]
-    fn test_res_init() {
-        // This mostly just tests that the weak linkage doesn't panic wildly...
-        res_init_if_glibc_before_2_26().unwrap();
-    }
-
-    #[test]
-    fn test_parse_glibc_version() {
-        let cases = [
-            ("0.0", Some((0, 0))),
-            ("01.+2", Some((1, 2))),
-            ("3.4.5.six", Some((3, 4))),
-            ("1", None),
-            ("1.-2", None),
-            ("1.foo", None),
-            ("foo.1", None),
-        ];
-        for &(version_str, parsed) in cases.iter() {
-            assert_eq!(parsed, parse_glibc_version(version_str));
-        }
-    }
-}

src/libstd/sys/unix/os.rs

@@ -569,3 +569,30 @@ fn parse_glibc_version(version: &str) -> Option<(usize, usize)> {
         _ => None
     }
 }
+
+#[cfg(all(test, target_env = "gnu"))]
+mod test {
+    use super::*;
+
+    #[test]
+    fn test_glibc_version() {
+        // This mostly just tests that the weak linkage doesn't panic wildly...
+        glibc_version();
+    }
+
+    #[test]
+    fn test_parse_glibc_version() {
+        let cases = [
+            ("0.0", Some((0, 0))),
+            ("01.+2", Some((1, 2))),
+            ("3.4.5.six", Some((3, 4))),
+            ("1", None),
+            ("1.-2", None),
+            ("1.foo", None),
+            ("foo.1", None),
+        ];
+        for &(version_str, parsed) in cases.iter() {
+            assert_eq!(parsed, parse_glibc_version(version_str));
+        }
+    }
+}