Harmonize WIN32 implementation of serial time-outs with Posix

This is from @mariusgreuel in Issue #1249.
#1249

> The WIN32 time-out is specified as ReadTotalTimeoutConstant + buflen * ReadTotalTimeoutMultiplier, which makes it potentially much longer than the Posix one (i.e. at least double). ReadIntervalTimeout is also set to timeout, which essentially renders the interval timeout ineffective, so IMHO, we should explicitly disable that feature.

Author: mcuee

src/ser_win32.c

@@ -88,8 +88,8 @@ static BOOL serial_w32SetTimeOut(HANDLE hComPort, DWORD timeout) // in ms
 {
 	COMMTIMEOUTS ctmo;
 	ZeroMemory (&ctmo, sizeof(COMMTIMEOUTS));
-	ctmo.ReadIntervalTimeout = timeout;
-	ctmo.ReadTotalTimeoutMultiplier = timeout;
+	ctmo.ReadIntervalTimeout = 0;
+	ctmo.ReadTotalTimeoutMultiplier = 0;
 	ctmo.ReadTotalTimeoutConstant = timeout;
 
 	return SetCommTimeouts(hComPort, &ctmo);