pkg/fileserver: remove deadcode

We don't need a stub implementation as this code should never end up
being imported on non windows platforms.

Signed-off-by: Paul Holzinger <pholzing@redhat.com>

pkg/fileserver/server_unsupported.go

@@ -1,15 +0,0 @@
-//go:build !windows
-
-package fileserver
-
-import (
-	"fmt"
-)
-
-func StartShares(mounts map[string]string) error {
-	if len(mounts) == 0 {
-		return nil
-	}
-
-	return fmt.Errorf("this platform does not support sharing directories")
-}