selftests: mm: fix some build warnings

Fix build warnings:
pagemap_ioctl.c:1154:38: warning: format `%s' expects a matching `char *' argument [-Wformat=]
pagemap_ioctl.c:1162:51: warning: format `%ld' expects argument of type `long int', but argument 2 has type `int' [-Wformat=]
pagemap_ioctl.c:1192:51: warning: format `%ld' expects argument of type `long int', but argument 2 has type `int' [-Wformat=]
pagemap_ioctl.c:1600:51: warning: format `%ld' expects argument of type `long int', but argument 2 has type `int' [-Wformat=]
pagemap_ioctl.c:1628:51: warning: format `%ld' expects argument of type `long int', but argument 2 has type `int' [-Wformat=]

Link: https://lkml.kernel.org/r/20231103182343.2874015-2-usama.anjum@collabora.com


Fixes: 46fd75d4 ("selftests: mm: add pagemap ioctl tests")
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>