lddtree : prefer RUNPATH value over RPATH, if both are fixed

[StudioEtrange]

If both RUNPATH and RPATH are fixed, both values will be returned by elf_rpath_binutils.

• First, only one value should be returned, or the lddtree do not use any rpath value
• Second, when both values exist, RUNPATH must be privileged over RPATH value

[ncopa]

If both RUNPATH and RPATH are fixed,

How can I create a test binary that has both RUNPATH and RPATH "fixed"?

[ncopa]

this was fixed in 367581e