[flashrom-gerrit] Change in flashrom[master]: Add -W options from Makefile into meson warning_flags

[Anastasia Klimchuk (Code Review)]

Attention is currently required from: Thomas Heijligen.
Anastasia Klimchuk has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/58561 )

Change subject: Add -W options from Makefile into meson warning_flags
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Patch Set 5:

(1 comment)

Commit Message:

https://review.coreboot.org/c/flashrom/+/58561/comment/de415b5d_2f3d1408 
PS4, Line 13: warning_level=2 means -Wall and -Wextra as it is set in
> Needs update. This is now in the next patch.

This is actually not needed in any patch, I discovered that warning_level=2 already sets -Wall and -Wextra.
I still wanted to mention in commit message, so that it is clear why -Wall and -Wextra and not needed in the patch. So I added info in commit message.
I tried to re-write it a bit, so that it is more clear.