wireless: define cipher/AKM suites using a macro

The spec writes cipher/AKM suites as something like 00-0F-AC:9,
but the part after the colon isn't hex, it's decimal, so that
we've already had a few mistakes (in other code, or unmerged
patches) to e.g. write 0x000FAC10 instead of 0x000FAC0A.

Use a macro to avoid that problem.

Reviewed-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>