Closes issue #21316: mark test_devpoll to be meaningfull only for Solaris

Lib/test/test_devpoll.py

@@ -9,10 +9,8 @@ import sys
 import unittest
 from test.support import TESTFN, run_unittest, cpython_only
 
-try:
-    select.devpoll
-except AttributeError:
-    raise unittest.SkipTest("select.devpoll not defined")
+if not hasattr(select, 'devpoll') :
+    raise unittest.SkipTest('test works only on Solaris OS family')
 
 
 def find_ready_matching(ready, flag):