mm/kmemleak: fix print format of pointer in pr_debug()

With 0x%p, the pointer will be hashed and print (____ptrval____) instead. 
And with 0x%pa, the pointer can be successfully printed but with duplicate
prefixes, which looks like:

 kmemleak: kmemleak_free(0x(____ptrval____))
 kmemleak: kmemleak_free_percpu(0x(____ptrval____))
 kmemleak: kmemleak_free_part_phys(0x0x0000000a1af86000)

Use 0x%px instead of 0x%p or 0x%pa to print the pointer. Then the print
will be like:

 kmemleak: kmemleak_free(0xffff9111c145b020)
 kmemleak: kmemleak_free_percpu(0x00000000000333b0)
 kmemleak: kmemleak_free_part_phys(0x0000000a1af80000)

Link: https://lkml.kernel.org/r/20231018102952.3339837-4-liushixin2@huawei.com


Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Patrick Wang <patrick.wang.shcn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>