On *_WAIT states do not raise errors

[pavelrevak]

https://github.com/cortexm/pyswd/blob/1fc3d8510d9c830db2585c34a6aee8322a2e163b/swd/stlink/init.py#L42

on slow commands (for example EEPROM write) it can raise error, although it is not an error, in that cases, just wait until it will be OK