Replaced the existing axi_tdd with the new version
* Added DEFAULT_POLARITY synth parameter and RO register
* Added TDD_STATUS register
* Added TDD_SYNC_RST feature
* Used the asy_ prefix for signals which are not synced
* Added logic to force the state from ARMED to RUNNING when startup_delay=0
* Added feature to finish the burst when the module is disabled before its completion
Signed-off-by: Ionut Podgoreanu <ionut.podgoreanu@analog.com>