Revert "fs: exfat: Update to v1.2.5"

This reverts commit 83f3480a4589a88f1725cf61b1c32bfe39f24f72.
Revert "fs: exfat: This is FS and not drivers"

This reverts commit fc8d12c480833e4528b7eff56b94ee636a111a30.