[S] Change in coreboot[master]: fmap/region: Call the munmap of access_dev in xlate_windows

[Bao Zheng (Code Review)]

Attention is currently required from: Jason Glenesk, Aaron Durbin, Furquan Shaikh, Marshall Dawson, Zheng Bao, Martin Roth, Fred Reitberger, Felix Held.

Bao Zheng has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/74259 )

Change subject: fmap/region: Call the munmap of access_dev in xlate_windows
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Patch Set 1:

(1 comment)

Patchset:

PS1: 
https://review.coreboot.org/c/coreboot/+/74260
In this CL, the munmap is needed every time the mmap is called to switch back to page 0.
From the region device and mapping, we can not know which windows we are going to munmap. Now it is a workaround to call the first windows's munmap.