Change in flashrom[master]: flashrom.8: add missing entry for `--flash-contents`

[Nico Huber (Code Review)]

Attention is currently required from:  Felix Singer, Angel Pons, Michael Niewöhner.
Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/57807 )

Change subject: flashrom.8: add missing entry for `--flash-contents`
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Patch Set 2: Code-Review+2

(1 comment)

File flashrom.8.tmpl:

https://review.coreboot.org/c/flashrom/+/57807/comment/00d44c68_380cb396 
PS2, Line 295: .BR <ref-file> .
Can we add something about the purpose? I guess people who understand
it right away, wouldn't have to look here anyway. For instance:

The file contents will be used to decide which parts of the flash need
  to be written. Providing this saves an initial read of the full flash
  chip. Be careful, if the provided data doesn't match the flash contents,
  results are undefined.