ubsan: Restore dependency on ARCH_HAS_UBSAN

While removing CONFIG_UBSAN_SANITIZE_ALL, ARCH_HAS_UBSAN wasn't correctly
depended on. Restore this, as we do not want to attempt UBSAN builds
unless it's actually been tested on a given architecture.

Reported-by: Masahiro Yamada <masahiroy@kernel.org>
Closes: https://lore.kernel.org/all/20240514095427.541201-1-masahiroy@kernel.org
Fixes: 918327e ("ubsan: Remove CONFIG_UBSAN_SANITIZE_ALL")
Link: https://lore.kernel.org/r/20240514233747.work.441-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>

lib/Kconfig.ubsan

@@ -4,6 +4,7 @@ config ARCH_HAS_UBSAN
 
 menuconfig UBSAN
 	bool "Undefined behaviour sanity checker"
+	depends on ARCH_HAS_UBSAN
 	help
 	  This option enables the Undefined Behaviour sanity checker.
 	  Compile-time instrumentation is used to detect various undefined