GH628: Add -help to all apps docs.

Signed-off-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
diff --git a/doc/apps/spkac.pod b/doc/apps/spkac.pod
index 553fd2d..f5ce8a6 100644
--- a/doc/apps/spkac.pod
+++ b/doc/apps/spkac.pod
@@ -7,6 +7,7 @@
 =head1 SYNOPSIS
 
 B<openssl> B<spkac>
+[B<-help>]
 [B<-in filename>]
 [B<-out filename>]
 [B<-key keyfile>]
@@ -29,6 +30,10 @@
 
 =over 4
 
+=item B<-help>
+
+Print out a usage message.
+
 =item B<-in filename>
 
 This specifies the input filename to read from or standard input if this