soc_core: uart: add a reset line to the UART

Enable resetting the UART by adding a ResetInserter to the UART.

The UART must be reset when resetting the softcore.

Signed-off-by: Sean Cross <sean@xobs.io>

litex/soc/integration/soc_core.py

@@ -148,7 +148,8 @@ class SoCCore(Module):
                 self.submodules.uart  = uart.UARTStub()
             else:
                 self.submodules.uart_phy = uart.RS232PHY(platform.request(uart_name), clk_freq, uart_baudrate)
-                self.submodules.uart = uart.UART(self.uart_phy)
+                self.submodules.uart = ResetInserter()(uart.UART(self.uart_phy))
+
         #else:
         #    del self.soc_interrupt_map["uart"]