Updated version of the STM32 USB driver.

Hi folks,

I have just uploaded a new version of the STM32 USB driver here:

www.zynaptic.com/ecos/packages/stm32-usb-20090601.epk

Changes from the last code drop are as follows:

1) Driver compilation is now switched on and off in CDL using the
'enable endpoiont 0' option.

2) Disabling devtab support is now a CDL constraint on using the driver.

3) CDL endpoint interfaces are now implemented so that the
CYGHWR_IO_USB_SLAVE_OUT_ENDPOINTS and CYGHWR_IO_USB_SLAVE_IN_ENDPOINTS
values are set correctly.  This should allow the serial slave class
driver to configure correctly, but it will still need patching to cope
with dynamic endpoints.

4) USB support is now added directly into the existing target.  See the
following post for how to safely remove it:
http://ecos.sourceware.org/ml/ecos-devel/2009-05/msg00079.html

5) Implemented the last functional TODO's in the source code.  Anything
now marked as a TODO is a feature that it would be nice to have, but
which is not essential to normal operation.

Chris.