Hello.

Following patch tries to resolve following 2 issues:

a) When one takes address of a function that uses target_clones attribute,
   default implementation is always returned.

b) Using dlsym("foo") should work and thus the resolver function should
   use the default name. Because of that, default implementation must be
   renamed.

Unfortunately, we currently do not support redirection of ipa_refs, thus
walk_tree is needed to resolve that. Hopefully there should not be any
different IPA_REF that needs to be handled.

Patch can bootstrap on x86_64-linux-gnu and survives regression tests.

Ready to be installed?
Martin