Data race in fakefs_evict_inode and fakefs_readpage (iSH+Linux)

I can dig into this later (time permitting) but for now just a screen grab:

Reproduce by building a project of your choosing (within iSH) with `make --jobs=X` set to anything greater than 1

Start by reproducing the report in iSH: build a project with `make --jobs=X` using X greater than 1. Then inspect the fakefs_evict_inode and fakefs_readpage paths shown in the report and determine how the data race occurs. Done means the reported race is addressed and the parallel build no longer reproduces it.

Written by the indexing model from the issue text.