Fix dirtying of the source tree when building tools

Our clean rule assumes all builds are done under debian/build/ and only that directory needs to be deleted. However perf and rtla currently don't build completely out-of-tree and do create a few files in their source trees. Apply patches to fix that.

This fixes building a source package after building binary packages. It is also ensures that these generated files won't get into the linux-source package when moving to a fully parallel build.

Closes: #1045765