docs: Fix 'Offline migration' description

'transfers inactive the definition of a domain' seems odd.
Signed-off-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: NAndrea Bolognani <abologna@redhat.com>

docs/migration.html.in

@@ -141,7 +141,7 @@
     <h2><a id="offline">Offline migration</a></h2>
 
     <p>
-      Offline migration transfers inactive the definition of a domain
+      Offline migration transfers the inactive definition of a domain
       (which may or may not be active). After successful completion, the
       domain remains in its current state on the source host and is defined
       but inactive on the destination host. It's a bit more clever than