depend-cleanup.sh: Simplify the logic, and clean bootstrap tools.

[des]

Summary

• There's no need to check if the file exists before grepping it; if it does not exist, grep will fail, which is what we want. Just redirect the error message to /dev/null.
• There's no need to split the .o and .pico cases; the bodies are identical, so combine the conditions. Use a glob to avoid a false negative if one exists but not the other.
• Also run depend-cleanup.sh on the bootstrap build tree. This unbreaks the build after 29c5f8bf9a01.

Sponsored by: Klara, Inc.
Sponsored by: NetApp, Inc.

[des]

I'm not 100% sure hardcoding tmp/obj-tools here is the best approach; perhaps we should simply run depend-cleanup.sh with OBJTOP=${WORLDTMP} before building bootstrap tools?

[des]

Remove unnecessary line continuations.

[emaste]

perhaps we should simply run depend-cleanup.sh with OBJTOP=${WORLDTMP} before building bootstrap tools?

Yeah, I think we should do that (or at least have the knowledge of what WORLDTMP is limited to Makefile.inc* rather than here).

FWIW the duplicated case was introduced in 838a061417300

[des]

Instead of hardcoding knowledge of tmp/obj-tools into depend-cleanup.sh, run it twice.

[imp]

Oh, I like this.