FPC: got RX working, got client over usart somehow working..., see detailed commit msg

* using WITH_FPC:
  * activate basic usart
  * no double buffer for now, no interrupt
  * usart_dataavailable/usart_readbuffer/usart_writebuffer, to demo it:
    * pm3 client over USB, minicom over usart
    * analyse a d 414243
* using WITH_FPC_HOST:
  * it implies WITH_FPC as it's based on it
  * control pm3 with client over usart
  * EXPERIMENTAL! still some frame desync issues
  * you can connect both from usart & USB with two pm3 clients
    * actually you *have* to connect USB for the moment because
      it's used to send debug messages about buggy usart... See Dbprintf_usb below
  * "sessions": msgs are directed to the latest client to have sent a cmd
  * Dbprintf_usb macro to send msgs to USB client to help debugging usart...
  * We now have an option to run client at different speed as usart is 115200:
    client/proxmark3 /dev/ttyUSB0 -b 115200
  * Consequently, argc,argv handling is a bit revamped, it was so messy...
  * USB and flashing are still at 460800, don't try flashing over usart yet ^^

client/comms.c

@@ -194,7 +194,7 @@ static void UsbCommandReceived(UsbCommand *c) {
 /*
 bool hookUpPM3() {
     bool ret = false;
-    sp = uart_open( comport );
+    sp = uart_open( comport, speed );
 
     if (sp == INVALID_SERIAL_PORT) {
         PrintAndLogEx(WARNING, "Reconnect failed, retrying...  (reason: invalid serial port)\n");
@@ -298,17 +298,17 @@ __attribute__((force_align_arg_pointer))
     return NULL;
 }
 
-bool OpenProxmark(void *port, bool wait_for_port, int timeout, bool flash_mode) {
+bool OpenProxmark(void *port, bool wait_for_port, int timeout, bool flash_mode, uint32_t speed) {
 
     char *portname = (char *)port;
     if (!wait_for_port) {
-        sp = uart_open(portname);
+        sp = uart_open(portname, speed);
     } else {
         PrintAndLogEx(SUCCESS, "Waiting for Proxmark to appear on " _YELLOW_("%s"), portname);
         fflush(stdout);
         int openCount = 0;
         do {
-            sp = uart_open(portname);
+            sp = uart_open(portname, speed);
             msleep(500);
             printf(".");
             fflush(stdout);