Change in flashrom[master]: programmer: Smoothen register_opaque_master() API

[Anastasia Klimchuk (Code Review)]

Attention is currently required from: Nico Huber, Edward O'Callaghan, Angel Pons.
Anastasia Klimchuk has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/54170 )

Change subject: programmer: Smoothen register_opaque_master() API
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Patch Set 1:

(1 comment)

File nicintel_eeprom.c:

https://review.coreboot.org/c/flashrom/+/54170/comment/f6061d13_08916697 
PS1, Line 489: return register_opaque_master(&opaque_master_nicintel_ee_82580, NULL);
My comment here: this has a piece of data (eecp), but the data was only passed to register_shutdown, and was not passed to register_opaque_master via opaque_master struct. Opaque master struct was const, and it stays const.