have WITH_CTF=YES imply DEBUG_FLAGS+=-g

[markj]

Summary

When WITH_CTF is set, we run ctfconvert on each object file after it's created, and ctfmerge on object files when linking. There's no point in doing this if there's no debug info, though. This change just sets DEBUG_FLAGS+=-g when WITH_CTF=YES. Additionally, I removed some superfluous checks in bsd.prog.mk and bsd.lib.mk.

Test Plan

Ran a "make tinderbox" with WITH_CTF=YES, no failures.

[imp]

Looks good to me.

[markj]

Closed by commit rS274200 (authored by @markj).