GUSBCFG TRDT fields have very particular meanings, and the field should be set
depending on your bus speed. There's no 8/16bit meaning in any current
reference manual for this field.
Fixes github issue #530
* USB host register definitions added.
* Extracted common register and bitfield definitions
from 'otg_fs.h' and 'otg_hs.h'
into new file 'otg_common.h'.
Modified usb low-level drivers to adopt to new style of bitfields.
* Fixed typo OTG_GOTGIN -> OTG_GOTGINT (according to the datasheet)
Signed-off-by: Amir Hammad <amir.hammad@hotmail.com>