Change in flashrom[master]: linux_mtd: Switch fopen() to open() for MTD devices

[Douglas Anderson (Code Review)]

Attention is currently required from: Hung-Te Lin, Edward O'Callaghan, Angel Pons, Patrick Rudolph.
Douglas Anderson has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/50206 )

Change subject: linux_mtd: Switch fopen() to open() for MTD devices
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Patch Set 1:

(1 comment)

Patchset:

PS1: 
Posted as requested by Hung-Te in https://review.coreboot.org/c/flashrom/+/50155.  This should have no impact at all other than just using the lower level API.

Hopefully someone can help test this?  I tested it downstream, but it looks like Chrome OS still has some forked changes from upstream.  Specifically there's a bunch of write protect stuff in that file downstream.  Luckily it as easy to just drop that part of the patch that touched the missing code, but I'd still appreciate any testing.  I'm a bit of a visitor in flashrom and I don't have a great way to test upstream.