Using sccache makes recompilation of rustc and Rust packages faster. This also makes the rust package visible in menuconfig, in order for the sccache options to be accessible. Signed-off-by: Jeffery To <jeffery.to@gmail.com>
They are for the target build which is not supported yet, drop them. Signed-off-by: Tianling Shen <cnsztl@immortalwrt.org>
Based on work from Donald Hoskins <grommish@gmail.com>. Signed-off-by: Luca Barbato <lu_zero@gentoo.org>