cvsimport: activate -a option, really.

An earlier commit ded9f400 added $opt_a support to disable the
cvsps grace period mechanism, but forgot to tell the option
parser about it.

Signed-off-by: Junio C Hamano <junkio@cox.net>

git-cvsimport.perl

@@ -85,7 +85,7 @@ sub write_author_info($) {
 	close ($f);
 }
 
-getopts("hivmkuo:d:p:C:z:s:M:P:A:S:L:") or usage();
+getopts("haivmkuo:d:p:C:z:s:M:P:A:S:L:") or usage();
 usage if $opt_h;
 
 @ARGV <= 1 or usage();