Fix nanos6 cross-compilation for riscv

pkgs/nanos6/default.nix

@@ -78,8 +78,6 @@ in
     ] ++
       (optional enableJemalloc "--with-jemalloc=${jemallocNanos6}") ++
       (optional enableGlibcxxDebug "CXXFLAGS=-D_GLIBCXX_DEBUG") ++
-      # Most nanos6 api symbols are resolved at runtime, so prefer
-      # ifunc by default
       (optional isCross "--with-symbol-resolution=ifunc");
 
     postConfigure = lib.optionalString (!enableDebug) ''