squashfs: fix incorrect argument to sizeof in kmalloc_array call

The sizeof(void *) is the incorrect argument in the kmalloc_array call, it
best to fix this by using sizeof(*cache_folios) instead.

Fortunately the sizes of void* and folio* happen to be the same, so this
has not shown up as a run time issue.

[akpm@linux-foundation.org: fix build]
Link: https://lkml.kernel.org/r/20250708142604.1891156-1-colin.i.king@gmail.com
Fixes: 2e227ff ("squashfs: add optional full compressed block caching")
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Cc: Phillip Lougher <phillip@squashfs.org.uk>
Cc: Chanho Min <chanho.min@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Author: ColinIanKing

fs/squashfs/block.c

@@ -89,7 +89,7 @@ static int squashfs_bio_read_cached(struct bio *fullbio,
 	int err = 0;
 #ifdef CONFIG_SQUASHFS_COMP_CACHE_FULL
 	struct folio **cache_folios = kmalloc_array(page_count,
-			sizeof(void *), GFP_KERNEL | __GFP_ZERO);
+			sizeof(*cache_folios), GFP_KERNEL | __GFP_ZERO);
 #endif
 
 	bio_for_each_folio_all(fi, fullbio) {