selftests/mm: include linux/mman.h

thuge-gen defines MAP_HUGE_* macros that are provided by linux/mman.h
since 4.15. Removes the macros and includes linux/mman.h instead.

Link: https://lkml.kernel.org/r/20240605223637.1374969-2-edliaw@google.com


Signed-off-by: Edward Liaw <edliaw@google.com>
Reviewed-by: Carlos Llamas <cmllamas@google.com>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: Bill Wendling <morbo@google.com>
Cc: Justin Stitt <justinstitt@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>