Fix 'wifionly' hint: -p is the wrong option here

OK tj@

Author: job

faq/faq4.html

@@ -507,7 +507,11 @@ <h2 id="WifiOnly">Bootstrapping Wireless Firmware</h2>
 # <b>vnconfig install76.img</b>
 vnd0
 # <b>mount /dev/vnd0a /mnt</b>
-# <b>fw_update -Fv -p /mnt iwm</b>
+# <b>cd /mnt</b>
+# <b>fw_update -Fv iwm</b>
+Get/Verify iwm-firmware-20240410.tgz ... done.
+fw_update: download iwm
+# <b>cd /</b>
 # <b>umount /mnt</b>
 # <b>vnconfig -u vnd0</b>
 </pre>