mm: page_alloc: fix building error on -Werror=array-compare

Arthur Marsh reported we would hit the error below when building kernel
with gcc-12:

  CC      mm/page_alloc.o
  mm/page_alloc.c: In function `mem_init_print_info':
  mm/page_alloc.c:8173:27: error: comparison between two arrays [-Werror=array-compare]
   8173 |                 if (start <= pos && pos < end && size > adj) \
        |

In C++20, the comparision between arrays should be warned.

Link: https://lkml.kernel.org/r/20211125130928.32465-1-sxwjean@me.comSigned-off-by: NXiongwei Song <sxwjean@gmail.com>
Reported-by: NArthur Marsh <arthur.marsh@internode.on.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

mm/page_alloc.c

@@ -8228,7 +8228,7 @@ void __init mem_init_print_info(void)
 	 */
 #define adj_init_size(start, end, size, pos, adj) \
 	do { \
-		if (start <= pos && pos < end && size > adj) \
+		if (&start[0] <= &pos[0] && &pos[0] < &end[0] && size > adj) \
 			size -= adj; \
 	} while (0)