selftests/mm: fix va_high_addr_switch.sh return value

selftests/mm: fix va_high_addr_switch.sh return value

Patch series "Fix va_high_addr_switch.sh test failure - again", v2.

The series address several issues exist for the va_high_addr_switch test:
1) the test return value is ignored in va_high_addr_switch.sh.
2) the va_high_addr_switch test requires 6 hugepages not 5.
3) the reurn value of the first test in va_high_addr_switch.c can be
   overridden by the second test.
4) the nr_hugepages setup in run_vmtests.sh for arm64 can be done in
   va_high_addr_switch.sh too.
5) update a comment for check_test_requirements.

This patch: (of 5)

The return value should be return value of va_high_addr_switch, otherwise
a test failure would be silently ignored.

Link: https://lkml.kernel.org/r/20251221040025.3159990-1-chuhu@redhat.com
Fixes: d9d957bd7b61 ("selftests/mm: alloc hugepages in va_high_addr_switch test")
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Reviewed-by: Luiz Capitulino <luizcap@redhat.com>
Cc: Luiz Capitulino <luizcap@redhat.com>
Cc: "David Hildenbrand (Red Hat)" <david@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>