This updates `mountRc` in `cmd/mountlib/rc.go` to parse options using the
unified `rc.ParseOptions` helper. It also enforces parameter validation by
calling `rc.CheckParamsUsed`.
- Replace custom options parsing with rc.ParseOptions for vfsOpt and mountOpt.
- Delete consumed params (mountPoint, mountType, fs) and call CheckParamsUsed
before initiating FUSE mount to reject unknown parameters.
- Clean up duplication tests (TestRcFlatOptions, TestRcFlatOptionsNull) in rc_test.go.
- Update TestRc in rc_test.go to pass a clean params map to unmount.Fn.
Hakan İSMAİLandNick Craig-Wood
e8ff1b123b