Adds the rust tools to the cross and native files if present so that
projects that use both rust and meson can build
(From OE-Core rev: 0ec40fa3aff233bd0dde0461299150786da956ef)
Signed-off-by: Joshua Watt <JPEWhacker@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>