Refactor usage flag formatting and implication
Refactor usage flag formatting and implication

When generating storage format tests, pass usage flags around as a list, and
format them as the last thing.

In Storagekey(), simplify the addition of implicit usage flags: this no
longer requires parsing.

The output is unchanged.

Signed-off-by: Gilles Peskine <f805f64266d288fc5467baa7be6cd0ff366f477b@arm.com>

ARMmbed/mbedtls,ARMmbed/mbedtls,Mbed-TLS/mbedtls,Mbed-TLS/mbedtls,ARMmbed/mbedtls,Mbed-TLS/mbedtls,ARMmbed/mbedtls,Mbed-TLS/mbedtls