xen/arm: mm: Do not dump the p2m when mapping a foreign gfn

xen/arm: mm: Do not dump the p2m when mapping a foreign gfn

The physmap operation XENMAPSPACE_gfmn_foreign is dumping the p2m when
an error occured by calling dump_p2m_lookup. But this function is not
using ratelimited printk.

Any domain able to map foreign gfmn would be able to flood the Xen
console.

The information wasn't not useful so drop it.

This is XSA-141.

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>