devel/freebsd-gcc14: External FreeBSD toolchain based on GCC 14.

[jhb]

Summary

This port provides external GCC toolchains for GCC 14.1.0 for the
aarch64, amd64, armv7, i386, powerpc, powerpc64, and riscv64
platforms.

[jhb]

Changes relative to devel/freebsd-gcc13:

• Dropped armv6 as a FLAVOR
• printf format patch had to be reworked due to upstream changes
• dropped a few patches from lang/gcc13 that were dropped in lang/gcc14
• Added some new headers to various pkg-plist

[jhb]

Simplify some bits for removing armv6

[imp]

The printf stuff looks like it's right, but I've not tested it. Once this is in, and pkg are available, I'll look again to redo what we're doing.

[jhb]

I should have noted that I've built an amd64 kernel and world with this (which did test the printf changes, I had to make changes to forward port the kprintf bits to 14 and had some bugs in my initial version).