Change in flashrom[master]: programmer.h: Convert anon union to anon struct

[Edward O'Callaghan (Code Review)]

Attention is currently required from: Sam McNally, Stefan Reinauer, Angel Pons.
Edward O'Callaghan has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/50246 )

Change subject: programmer.h: Convert anon union to anon struct
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Patch Set 3:

(2 comments)

Commit Message:

https://review.coreboot.org/c/flashrom/+/50246/comment/6e0de756_650c5f98 
PS2, Line 29: printf("%d\n", *foo.b);
I just removed it to avoid confusion.
> Still, I believe this change is a good idea: it's better to have null pointers than non-null but invalid pointers.

Indeed that's the idea.

File programmer.h:

https://review.coreboot.org/c/flashrom/+/50246/comment/78e8b15e_4ac8fed1 
PS2, Line 752: 	struct {
> This will need corresponding updates to ensure unused masters are zeroed out.

Done