[M] Change in flashrom[master]: [WIP] test_build.sh: Rework programmer selection using Meson

[Nico Huber (Code Review)]

Attention is currently required from: Felix Singer, Angel Pons.

Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/68068 )

Change subject: [WIP] test_build.sh: Rework programmer selection using Meson
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Patch Set 4:

(3 comments)

File meson.build:

https://review.coreboot.org/c/flashrom/+/68068/comment/55553da6_3c5c0548 
PS4, Line 641: programmers_available = []
Is it possible to concatenate a string instead? so that we don't have to
parse things like the colons later in the shell?

File test_build.sh:

https://review.coreboot.org/c/flashrom/+/68068/comment/3c883fb2_d4cf34af 
PS4, Line 49: env
Does it run in a shell? Meson docs don't seem to specify this :-/

If it does, we could make this much shorter, like `echo $FLASHROM_ALL_PROGRAMMERS`.

If it doesn't, we could still squash the rest of the pipe into a single sed
call, e.g. `sed -n -e 's/:/ /g' -e 's/^FLASHROM_ALL_PROGRAMMERS=//p'`.

https://review.coreboot.org/c/flashrom/+/68068/comment/d2e20453_3ac23c3c 
PS4, Line 53: 	echo ${programmer_list}
We don't need this indirection with the variable. As there is no other
output expected, we can let the meson command / pipe above print directly.