Change in flashrom[master]: flashrom: Convert do_read() into a libflashrom user

[Nico Huber (Code Review)]

Attention is currently required from: Edward O'Callaghan, Daniel Campello, Anastasia Klimchuk.
Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/59291 )

Change subject: flashrom: Convert do_read() into a libflashrom user
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Patch Set 4:

(3 comments)

File cli_classic.c:

https://review.coreboot.org/c/flashrom/+/59291/comment/51f2db08_7b1be3f8 
PS4, Line 635: 			if (map_flash(&flashes[0]) != 0) {
             : 				free(flashes[0].chip);
             : 				ret = 1;
             : 				goto out_shutdown;
             : 			}
             : 			msg_cinfo("Please note that forced reads most likely contain garbage.\n");
             : 			ret = do_read(&flashes[0], filename);
             : 			unmap_flash(&flashes[0]);
Mapping/unmapping is redundant with the calls in prepare_/finalize_flash_access().
Results are probably undefined.

I guess this might have been done on purpose to avoid the checks in prepare_flash_access().

File flashrom.c:

https://review.coreboot.org/c/flashrom/+/59291/comment/8e65c595_64fc1380 
PS4, Line 1935: 	}
Looks redundant given the checks in prepare_flash_access()?

https://review.coreboot.org/c/flashrom/+/59291/comment/76b6ea56_d4961c90 
PS4, Line 2169: 1024
KiB?