patchbomb: -c is not an alias for the --confirm option

The help text shows "-c/--confirm", which implies that -c is an alias
for --confirm.  Actually, it is an alias for --cc.  Correct the text
by removing -c.

hgext/patchbomb.py

@@ -199,7 +199,7 def patchbomb(ui, repo, *revs, **opts):
 
     Finally, the patch itself, as generated by :hg:`export`.
 
-    With the -d/--diffstat or -c/--confirm options, you will be presented
+    With the -d/--diffstat or --confirm options, you will be presented
     with a final summary of all messages and asked for confirmation before
     the messages are sent.