Merge pull request #9172 from tfc/bad-moves

Fix/remove some bad std::moves

(cherry picked from commit 8c049a9f044569ebda70231709f6f15d3073894a)
Change-Id: I720273378d2506a13883acee28abd096d099b0d4

src/libexpr/paths.cc

@@ -4,7 +4,7 @@ namespace nix {
 
 SourcePath EvalState::rootPath(CanonPath path)
 {
-    return std::move(path);
+    return path;
 }
 
 }