libct/utils: ResolveRootfs: remove

Since commit 8850636eb3 (February 2015) this function is no longer
used (replaced by (*ConfigValidator).rootfs), so let's remove it,
together with its unit tests (which were added by commit 917c1f6d6 in
April 2016).

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>

libcontainer/utils/utils.go

@@ -33,16 +33,6 @@ func init() {
 	}
 }
 
-// ResolveRootfs ensures that the current working directory is
-// not a symlink and returns the absolute path to the rootfs
-func ResolveRootfs(uncleanRootfs string) (string, error) {
-	rootfs, err := filepath.Abs(uncleanRootfs)
-	if err != nil {
-		return "", err
-	}
-	return filepath.EvalSymlinks(rootfs)
-}
-
 // ExitStatus returns the correct exit status for a process based on if it
 // was signaled or exited cleanly
 func ExitStatus(status unix.WaitStatus) int {