Change in coreboot[master]: Documentation: gpio: Update table as per coreboot guidelines

[Michael Niewöhner (Code Review)]

Attention is currently required from: Subrata Banik, Angel Pons, Eric Lai, Felix Held.
Michael Niewöhner has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/63126 )

Change subject: Documentation: gpio: Update table as per coreboot guidelines
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Patch Set 1:

(2 comments)

File Documentation/getting_started/gpio.md:

https://review.coreboot.org/c/coreboot/+/63126/comment/6696cd39_d12ecfc6 
PS1, Line 177: (GPP: RSMRST,  
this won't work - just tested this locally. You have to prefix the lines to make the cell become a multiline cell:

```
+------------------------+----------------+-------------+-------------+
| | 00 - Power Good      |  Warm Reset    |     N       |    N        |
| | (GPP: RSMRST,        +----------------+-------------+-------------+
| | GPD: DSW_PWROK)      |  Cold Reset    |     N       |    N        |
+------------------------+----------------+-------------+-------------+
```

https://review.coreboot.org/c/coreboot/+/63126/comment/79805243_7d9bf281 
PS1, Line 212: 11 - Resume Reset      |  Warm Reset    |     -       |    N        |
             : |  (GPP: Reserved,       +----------------+-------------+-------------+
             : |   GPD:
prefix | needed as above