config: hide entries when in backend mode

This implies hidding entries for:
- binutils libraries
- dmalloc
- duma
- native gdb
- ltrace
- strace
- sstrip

 reporter_name="Ioannis E. VENETIS"

 reporter_url="http://sourceware.org/ml/crossgcc/2009-11/msg00109.html"

 reporter_comment=""