Change in flashrom[master]: tests: Add comprehensive comment for chip.c

[Edward O'Callaghan (Code Review)]

Attention is currently required from: Nico Huber, Angel Pons, Anastasia Klimchuk.
Edward O'Callaghan has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/59238 )

Change subject: tests: Add comprehensive comment for chip.c
......................................................................

Patch Set 4:

(2 comments)

Commit Message:

https://review.coreboot.org/c/flashrom/+/59238/comment/3067252b_6f365ac2 
PS4, Line 8: 
```
The following describes the two mechanisms of testing done for flash chip operations.

BUG=?
TEST=none
```

File tests/chip.c:

https://review.coreboot.org/c/flashrom/+/59238/comment/ba543e61_d3f3d3d2 
PS4, Line 30: Importantly
            :  * there are two types of tests here, corresponding to two ways of
            :  * emulating a chip:
This is all very difficult and verbose sentence to parse. I think you are really only just saying the following short sharp points.

```
Two flash chip test variants are used:

i ) Mock chip state backed by `g_chip_state` and,
ii) Mock chip operations backed by `dummyflasher` emulation.
```

It is odd to have this comment juxtaposition next to to `g_chip_state` as only part (i) is relevant to it. A better position would be after the license as a preamble to the files content.