mm: use stack_depot for recording kmemleak's backtrace

Using stack_depot to record kmemleak's backtrace which has been
implemented on slub for reducing redundant information.

[akpm@linux-foundation.org: fix build - remove now-unused __save_stack_trace()]
[zhaoyang.huang@unisoc.com: v3]
  Link: https://lkml.kernel.org/r/1667101354-4669-1-git-send-email-zhaoyang.huang@unisoc.com
[akpm@linux-foundation.org: fix v3 layout oddities]
[akpm@linux-foundation.org: coding-style cleanups]
Link: https://lkml.kernel.org/r/1666864224-27541-1-git-send-email-zhaoyang.huang@unisoc.com
Signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: ke.wang <ke.wang@unisoc.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zhaoyang Huang <huangzhaoyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>