serial: fix blocking call on ports, esp. on win32

Summary from Lada:

On Win7, good testing command is:
C:\hamlib> rigctl -vvvvv -m 214 -r COM1 -s 4800 -C data_bits=8 -C
stop_bits=2 -C serial_handshake=Hardware -C timeout=1000

Behavior of this command differs on COM port. On hardware ports
(onboard, PCI NetMos, all probably 16550-compatible) rigctl freeze in
data write. It is correct, no hardware handshake is estabilished. On
FT232 USB port initialization failed by timeout. I think it is not
correct but this is not subject of this e-mail.

Looked into hamlib source and found, that timeout argument is no
longer handled. SetCommTimeouts takes timeout from c_cc[VTIME] which
is not filled.

Signed-off-by: Ladislav Vaiz <spam@nagano.cz>

src/serial.c

@@ -1,6 +1,6 @@
 /*
  *  Hamlib Interface - serial communication low-level support
- *  Copyright (c) 2000-2010 by Stephane Fillod
+ *  Copyright (c) 2000-2013 by Stephane Fillod
  *  Copyright (c) 2000-2003 by Frank Singleton
  *  Parts of the PTT handling are derived from soundmodem, an excellent
  *  ham packet softmodem written by Thomas Sailer, HB9JNX.
@@ -346,6 +346,11 @@ int HAMLIB_API serial_setup(hamlib_port_t *rp)
   sg.sg_flags = RAW;
 #endif
 
+  /*
+   * VTIME in deciseconds, rp->timeout in miliseconds
+   */
+  options.c_cc[VTIME] = rp->timeout / 100;
+  options.c_cc[VMIN] = 1;
 
   /*
    * Flush serial port