Add get and set accessors for jtag_speed:

- Setter calls the interface driver callback to improve core encapsulation.
- Use getter in standard JTAG interface drivers and ZY1000 minidriver.


git-svn-id: svn://svn.berlios.de/openocd/trunk@2159 b42882b7-edfa-0310-969c-e2dbd0fdcd60

src/jtag/zy1000/zy1000.c

@@ -356,7 +356,7 @@ int zy1000_init(void)
 
 	 /* deassert resets. Important to avoid infinite loop waiting for SRST to deassert */
 	zy1000_reset(0, 0);
-	zy1000_speed(jtag_speed);
+	zy1000_speed(jtag_get_speed());
 
 	return ERROR_OK;
 }