- there was a small race in `uart_pattern_link_free`:
`rx_pattern_pos.data` was accessed for reading outside spinlock
- `uart_flush_input` enabled
`UART_INTR_RXFIFO_FULL|UART_INTR_RXFIFO_TOUT` intr mask on exit even
if these flags weren't set when function was called
Closes https://github.com/espressif/esp-idf/pull/7023