icE1usb fw: Add GPIO access functions

The 32 bit register is split in different fields to speed up
access to the 'in' field. The oe/out fields can't be split because
all writes are 32 bit wide (i.e. no support for byte enable in the
gateware)

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
Change-Id: Ic25377bb777e5d25939f0e8cfe6b7c6ef8641f6d
2 files changed