AOSP: Include private/fs_config.h directly when needed

This is no longer a transitive include of android_filesystem_config.h

Bug: 149785767
Test: build
Change-Id: I954adf7879fa811eb2b290a0983c84d47ecae26c
From AOSP commit: 9fa6bed983d5ddd7226af647a0c4c0d922227be4
1 file changed