[v9_9] handle time units in dnssec-coverage -r

4174.	[bug]		"dnssec-coverage -r" didn't handle time unit
			suffixes correctly. [RT #38444]

bin/python/dnssec-coverage.py.in

@@ -326,7 +326,7 @@ def vspace():
     if _firstline:
         _firstline = False
     else:
-        print()
+        print('')
 
 ############################################################################
 # vreset:
@@ -664,7 +664,7 @@ def parse_args():
     parser.add_argument('-d', dest='keyttl', type=str,
                         help='the DNSKEY TTL', metavar='int')
     parser.add_argument('-r', dest='resign', default='1944000', 
-                        type=int, help='the RRSIG refresh interval '
+                        type=str, help='the RRSIG refresh interval '
                                        'in seconds [default: 22.5 days]',
                         metavar='int')
     parser.add_argument('-c', dest='compilezone',