Function cose_signature_get_unprotected

pub unsafe extern "C" fn cose_signature_get_unprotected(
    signature: *mut cose_signature_t,
    hdr: *mut cose_hdr_t,
    key: i32,
) -> bool

@brief Retrieve an unprotected header from a signature object by key lookup

@param signature The signature object to operate on @param hdr hdr struct to fill @param key The key to look up

@return A protected header object with matching key @return NULL if there is no header with the key