controller: add commissioner-side commissioning building blocks #2734

Job	Run time
build_and_test (rustcrypto, os)	25m 39s
build_and_test (rustcrypto)	9m 27s
build_and_test (mbedtls)	8m 9s
build_and_test (rustcrypto, alloc)	6m 54s
build_and_test (openssl, alloc)	6m 51s
build_and_test (openssl)	6m 59s
build_and_test (mbedtls, alloc)	7m 36s
build_and_test (openssl, os)	9m 47s
build_and_test (mbedtls, os)	11m 34s
	1h 32m 56s

Provide feedback