FindBinUtils: Add more Utils, including llvm drop-ins
Added some LLVM drop-in replacements.
A couple tools like readelf were missing, now most commonly used and generic binutils are available as CMake variable.
The choice is a bit arbitrary, but more special-use stuff like gcof is left out.
readelf: Commonly used as alternative to objdump addr2line: Needed to decode raw backtraces llvm-symbolizer: Alternative to addr2line (but not a drop-in)