Suppress socket imports that might not exist on some systems (#2916)

* Suppress socket imports that might not exist on some systems

Author: CoolCat467

src/trio/socket.py

@@ -70,10 +70,16 @@
 if sys.implementation.name == "cpython":
     from socket import (
         if_indextoname as if_indextoname,
-        if_nameindex as if_nameindex,
         if_nametoindex as if_nametoindex,
     )
 
+    # For android devices, if_nameindex support was introduced in API 24,
+    # so it doesn't exist for any version prior.
+    with _suppress(ImportError):
+        from socket import (
+            if_nameindex as if_nameindex,
+        )
+
 
 # not always available so expose only if
 if sys.platform != "win32" or not _t.TYPE_CHECKING: