Enable .init_array and .fini_array with xtoolchain GCC.

[jhb]

Summary

For base/gcc, only enable .init_array and .fini_array for 12.0 and later
to match the policy used by clang and llvm. For the xtoolchain ports,
enable these unconditionally since the only OS version handy is the OS
version of the build host, not the target OS to be built. Unlike llvm,
the use of .init_array and .fini_array is set at compile-time for GCC
and can't be changed at runtime.

Bump PORTREVISION for base/gcc and the xtoolchain GCC ports.

Test Plan

• built and ran a FreeBSD/mips world with this enabled. The native self-hosted world is still trying to finish, but it has made sufficient progress that it should be using some cross-tools built with the base/gcc native compiler.

[bdrewery]

Do these need PORTREVISION bumps?

[jhb]

Yes, they probably will need those. I wanted to get feedback for the idea of how these are enabled (if we wanted to do something with OSVERSION, etc.) first and then add the bumps to the final candidate patch.

[bapt]

accepted with a bump of portrevision

[jhb]

• Make init/fini conditional on OSVERSION for base/gcc.
• Add PORTREVISION bumps.

[jhb]

devel/powerpc64-gcc/Makefile

46

I still think I can't really make this one conditional b/c we don't know the target OS version (OSVERSION is the OS version of the build host, not the target we are planning to build).

[jhb]

• Don't enable init_array/fini_array for arm-none-eabi-gcc and aarch64-none-elf-gcc.