xen-livepatch: fix --force option comparison

The check for --force option shouldn't be against 0.

Reported-by: Jan Beulich <jbeulich@suse.com>
Fixes: 62a72092a5 ('livepatch: introduce --force option')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Ross Lagerwall <ross.lagerwall@citrix.com>

tools/misc/xen-livepatch.c

@@ -576,7 +576,7 @@ int main(int argc, char *argv[])
         return 0;
     }
 
-    if ( strcmp("--force", argv[1]) )
+    if ( !strcmp("--force", argv[1]) )
     {
         if ( argc <= 2 )
         {