Should call $triplet-objcopy, $triplet-readelf etc.

Binary package hint: pkg-create-dbgsym

Hey

To support cross-compilation, we're (slowly) transitioning the world to call $triplet-strip instead of strip for all binutils (e.g. readelf, objcopy, objdump etc.) when cross-compiling.

This is important for two reasons, first because binutils-multiarch might not be installed, and hence $triplet-$util might be the only thing which works, and second because even if binutils-multiarch is installed, the cross-build might target an architecture which it doesn't support yet (typically, when bootstraping an architecture)

Here's a list of things which we need to do in pkg-create-dbgsym:
- call dpkg-architecture to figure the triplet of the arch we're building for
- replace calls to readelf/objcopy/objdump/strip/etc. in pkg_create_dbgsym and other places; probably pkg_create_dbgsym and dh_strip (albeit it doesn't seem to do any direct calls right now)
- (optional) I'm not sure how useful it is to cross-build pkg-create-dbgsym itself, since it's arch: all; there are some places in the testsuite which would need patching to cross-build

Thanks,