build: check that all banked functions are defined correctly

[jorgegv]

Functions that are migrated to banked_code directory need to have 3 definitions:

• Add a new ID macro for the function to memory.h
• Add its new function call macro to memory.h
• Add its ID to 00main.asm table so that the memory_call_banked_function... functions can find the banked functions

The build process needs to check that each banked function is defined correctly in all places, because in several ocassions some of the steps were forgotten and it led to long debugging times until I noticed the missing step.

Tasks:

• Create a script that checks that banked functions are defined fully and correctly
• Integrate that script in the build process (Makefile ) so that build fails if any banked function is not correctly defined

[jorgegv]

merged in 277a488