selftests/mm: fix build warnings on ppc64
Fix warnings like:
In file included from uffd-unit-tests.c:8:
uffd-unit-tests.c: In function `uffd_poison_handle_fault':
uffd-common.h:45:33: warning: format `%llu' expects argument of type
`long long unsigned int', but argument 3 has type `__u64' {aka `long
unsigned int'} [-Wformat=]
By switching to unsigned long long for u64 for ppc64 builds.
Link: https://lkml.kernel.org/r/20240521030219.57439-1-mpe@ellerman.id.au
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>