PCI/P2PDMA: Constify 'struct bin_attribute'

The sysfs core now allows instances of 'struct bin_attribute' to be
moved into read-only memory. Make use of that to protect them against
accidental or malicious modifications.

Link: https://lore.kernel.org/r/20241202-sysfs-const-bin_attr-pci-v1-3-c32360f495a7@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>

drivers/pci/p2pdma.c

@@ -161,7 +161,7 @@ static int p2pmem_alloc_mmap(struct file *filp, struct kobject *kobj,
 	return ret;
 }
 
-static struct bin_attribute p2pmem_alloc_attr = {
+static const struct bin_attribute p2pmem_alloc_attr = {
 	.attr = { .name = "allocate", .mode = 0660 },
 	.mmap = p2pmem_alloc_mmap,
 	/*
@@ -180,14 +180,14 @@ static struct attribute *p2pmem_attrs[] = {
 	NULL,
 };
 
-static struct bin_attribute *p2pmem_bin_attrs[] = {
+static const struct bin_attribute *const p2pmem_bin_attrs[] = {
 	&p2pmem_alloc_attr,
 	NULL,
 };
 
 static const struct attribute_group p2pmem_group = {
 	.attrs = p2pmem_attrs,
-	.bin_attrs = p2pmem_bin_attrs,
+	.bin_attrs_new = p2pmem_bin_attrs,
 	.name = "p2pmem",
 };