Improve error when compiling a derive macro with -Z sanitizer

[software-opal]

I'm trying to build some code with the address sanitiser on; and I run into this error:

Compiling failure_derive v0.1.5
error: Only executables, staticlibs, cdylibs, dylibs and rlibs can be compiled with `-Z sanitizer`
error: aborting due to previous error
error: Could not compile `failure_derive`.
error: build failed

After some googling the solution appears to be(from #48199) to use --target=.... I was wondering if the message could be improved to something like:

Compiling failure_derive v0.1.5
error: Only executables, staticlibs, cdylibs, dylibs and rlibs can be compiled with `-Z sanitizer`
hint: Try running the command again, and specifying a target triple; e.g. `--target=x86_64-unknown-linux-gnu`
error: aborting due to previous error
error: Could not compile `failure_derive`.
error: build failed