Create a single pkg-plist that uses arch-specific PLIST_SUBs to control
arch-specific linker scripts but is otherwise machine-independent.
- Only include objcopy for OS versions older than 11.0 (11.0 uses the elftoolchain elfcopy as objcopy in the base system)
- Use %%BUTARGET%% throughout. This probably fixes the sparc64 pkg-plist which was not updated when BUTARGET started including OSREL. This also avoids hardcoding an OSREL of 12.0 for powerpc64.
- Enable MIPS ldscripts for all MIPS architectures which probably fixes this port on mips64 and mipsn32.
- Enable PowerPC ldscripts for all PowerPC architectures which probably fixes this port on powerpc.