[tock] rewrite GPIO to use autogenerated register map

[mazurek-michal]

Pull Request Overview

This pull request replace GPIO register definitions with auto-generated register map form OpenTitan project.

Testing Strategy

Run TockOS kernel with Opentitan app hello.

TODO or Help Wanted

N/A

Documentation Updated

• [x] No updates are required.

Formatting

• [x] Ran make prepush.

[mazurek-michal]

Size difference analysis

Result generated by command:

make clean
make flash

• 8e84b371f (HEAD -> gpio_regs, origin/gpio_regs) chip/lowrisc Rewrite GPIO to use only direct IO.
• 75f22d593 [tock] Rewrite GPIO to use autogenerated register map
• 64c8ecb3d chip/lowrisc Update lowrisc autogenerated registers definitions
• e1dc0cbb3 (origin/opentitan-master, opentitan-master) Add simpel instruction how to flash cw310 bitstream

hash	name	text	data	bss	dec	hex	diff
e1dc0cbb3	baseline	140518	28	13280	153826	258e2	0
64c8ecb3d	regs update	140518	28	13280	153826	258e2	0
75f22d593	GPIO new regs	143174	28	13280	156482	26342	+2656
8e84b371f	GPIO direct bitfield	142230	28	13280	155538	25f92	+1712

[mazurek-michal]

@cfrantz LGTM