esp_sha() function

For more versatile SHA calculations, where data doesn't need to be passed all at once, try the mbedTLS mbedtls/shaX.h APIs. The hardware-accelerated mbedTLS implementation is also faster when hashing large amounts of data. It is not necessary to lock any SHA hardware before calling this function, thread safety is managed internally. If a TLS connection is open then this function may block indefinitely waiting for a SHA engine to become available. Use the mbedTLS SHA API to avoid this problem.