Fix the error in the raise statement of check_positive()

1. In the raise statement of the check_positive() function, the error message conflicts with the if condition.
2. If the value of val is 0, it passes the if condition but raises an error message stating [0 has to be >= 0].
3. This PR removes the = from the raise statement, so when val is 0,
it will correctly prompt that the value of val [has to be > 0].

Signed-off-by: dufuhang <dufuhang@kylinos.cn>

tuned-adm.py

@@ -34,7 +34,7 @@ def check_positive(value):
 	except ValueError:
 		val = -1
 	if val <= 0:
-		raise argparse.ArgumentTypeError("%s has to be >= 0" % value)
+		raise argparse.ArgumentTypeError("%s has to be > 0" % value)
 	return val
 
 def check_log_level(value):