update section names to comply with rgbds redefinitions

https://github.com/bentley/rgbds/commit/7770827cce8029310c05d93fa9232a3620689ef5 so bentley's gone and renamed everything since a bunch of new section types were added anyway, so if we want wram/vram/sram banks we gotta cut off outdated versions of rgbds. pokecrystal uses all three so this is inevitable

a rundown of whats changed:

HOME -> ROM0
DATA, CODE -> ROMX
BSS -> WRAM0, WRAMX

new to rgbds are banked VRAM and SRAM