ubsan: remove cc-option test for UBSAN_TRAP

-fsanitize-undefined-trap-on-error has been supported since GCC 5.1 and
Clang 3.2.  The minimum supported version of these according to
Documentation/process/changes.rst is 5.1 and 11.0.0 respectively. Drop
this cc-option check.

Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230407215406.768464-1-ndesaulniers@google.com