selftests/lkdtm: Add UBSAN config

UBSAN_BOUNDS and UBSAN_TRAP depend on UBSAN config option.
merge_config.sh script generates following warnings if parent config
doesn't have UBSAN config already enabled and UBSAN_BOUNDS/UBSAN_TRAP
config options don't get added to the parent config.

Value requested for CONFIG_UBSAN_BOUNDS not in final .config
Requested value: CONFIG_UBSAN_BOUNDS=y
Actual value:

Value requested for CONFIG_UBSAN_TRAP not in final .config
Requested value: CONFIG_UBSAN_TRAP=y
Actual value:

Fix this by including UBSAN config.

Fixes: c75be56e35b2 ("lkdtm/bugs: Add ARRAY_BOUNDS to selftests")
Signed-off-by: Muhammad Usama Anjum <[e-mail]>
Acked-by: Kees Cook <[e-mail]>
Signed-off-by: Shuah Khan <[e-mail]>

tools/testing/selftests/lkdtm/config

···
 CONFIG_HARDENED_USERCOPY=y
 CONFIG_RANDOMIZE_KSTACK_OFFSET_DEFAULT=y
 CONFIG_INIT_ON_ALLOC_DEFAULT_ON=y
+CONFIG_UBSAN=y
 CONFIG_UBSAN_BOUNDS=y
 CONFIG_UBSAN_TRAP=y
 CONFIG_STACKPROTECTOR_STRONG=y