purge linker scripts of macro-based meta-language

[zephyrbot]

Reported by Andrew Boie:

Our linker scripts are a confusing read to someone used to standard GNU LD scripts.
We have all these macros in include/linker-tool-gcc and other places that are artifacts from a distant time when we were trying to support the oddball Diab compiler.

Go through all the linker scripts, expand all these macros to just standard LD syntax. If we need to keep any macros to support XIP do so where it makes sense.

We should also move the OUTPUT_FORMAT() declarations in linker-tool-gcc into the arch-specific linker scripts.

(Imported from Jira ZEP-2282)