PM: hibernate: Use vmalloc_array() and vcalloc() to improve code

Remove array_size() calls and replace vmalloc() and vzalloc() with
vmalloc_array() and vcalloc() respectively to simplify the code in
save_compressed_image() and load_compressed_image().

vmalloc_array() is also optimized better, resulting in less
instructions being used, and vmalloc_array() handling overhead is
lower [1].

Link: https://lore.kernel.org/lkml/abc66ec5-85a4-47e1-9759-2f60ab111971@vivo.com/

 [1]
Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>
Link: https://patch.msgid.link/20250817083636.53872-1-rongqianfeng@vivo.com


[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>