filesystem: disallow path traversal in FS_Delete and FS_Rename #2820

Job	Run time
flatpak (su.xash.Engine.Compat.i386)	3m 53s
build (ubuntu-20.04, linux, amd64)	3m 8s
build (ubuntu-20.04, linux, i386)	3m 37s
build (ubuntu-20.04, linux, arm64, true)	4m 38s
build (ubuntu-20.04, linux, armhf, true)	4m 3s
build (ubuntu-20.04, linux, riscv64, true)	4m 6s
build (ubuntu-20.04, linux, ppc64el, true)	4m 28s
build (ubuntu-20.04, android, multiarch)	11m 31s
build (ubuntu-latest, nswitch, arm64)	3m 20s
build (ubuntu-latest, psvita, armv7hf)	8m 5s
build (windows-latest, win32, amd64)	2m 45s
build (windows-2019, win32, i386)	2m 44s
build (macos-14, apple, arm64)	1m 30s
build (macos-13, apple, amd64)	2m 20s
Upload releases	51s
	1h 0m 59s

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