mm/debug_page_alloc: improve error message for invalid guardpage minorder

When an invalid debug_guardpage_minorder value is provided, include the
user input in the error message.  This helps users and developers diagnose
configuration issues more easily.

No functional change.

Link: https://lkml.kernel.org/r/20250427100442.958352-3-ye.liu@linux.dev


Signed-off-by: Ye Liu <liuye@kylinos.cn>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>