[M] Change in flashrom[main]: libflashrom: Add set log level functionality

[Anastasia Klimchuk (Code Review)]

Attention is currently required from: Dmitry Zhadinets.

Anastasia Klimchuk has posted comments on this change by Dmitry Zhadinets. ( https://review.coreboot.org/c/flashrom/+/87047?usp=email )

Change subject: libflashrom: Add set log level functionality
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Patch Set 6:

(4 comments)

Patchset:

PS6: 
Thank you! you implemented a TODO which was here for so long!

File libflashrom.c:

https://review.coreboot.org/c/flashrom/+/87047/comment/2dd0092e_c0533fd0?usp... :
PS6, Line 6:  *
I think it's about time to add a line for yourself here, and in the header, you are doing significant changes (and there are even more changes coming next)

File tests/libflashrom.c:

https://review.coreboot.org/c/flashrom/+/87047/comment/b484f27b_6124910d?usp... :
PS6, Line 66: 	(void)state; /* unused */
            : 	int user_data = 100500;
            : 	flashrom_set_log_callback_v2(test_log_callback_v2, &user_data);
            : 	flashrom_set_log_level(FLASHROM_MSG_WARN);
For readability, could you please re-arrange lines a bit, and add few new lines:

```
(void)state; /* unused */

flashrom_set_log_level(FLASHROM_MSG_WARN);
    
/* v2 API check */
int user_data = 100500;
flashrom_set_log_callback_v2(test_log_callback_v2, &user_data);
....and the rest of the block as is
```

flashrom_set_log_level makes impact on all the code below, so I wanted it to be more visible

https://review.coreboot.org/c/flashrom/+/87047/comment/f5fae930_92454a7d?usp... :
PS6, Line 91: 	/* check that callback is called after the change*/
maybe a new line between 90-91, again so that flashrom_set_log_level be easily visible