skbuff: constify skb_propagate_pfmemalloc() "page" argument

mainline inclusion
from mainline-v5.12-rc1-dontuse
commit 48f971c9
category: feature
bugzilla: 173966
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=48f971c9c80a728646fc03367a28df747f20d0f4

----------------------------------------------------------------------

The function doesn't write anything to the page struct itself,
so this argument can be const.

Misc: align second argument to the brace while at it.
Signed-off-by: NAlexander Lobakin <alobakin@pm.me>
Reviewed-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>
Reviewed-by: NYongxin Li <liyongxin1@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

include/linux/skbuff.h

@@ -2927,7 +2927,7 @@ static inline struct page *dev_alloc_page(void)
  *	@page: The page that was allocated from skb_alloc_page
  *	@skb: The skb that may need pfmemalloc set
  */
-static inline void skb_propagate_pfmemalloc(struct page *page,
+static inline void skb_propagate_pfmemalloc(const struct page *page,
 					    struct sk_buff *skb)
 {
 	if (page_is_pfmemalloc(page))