Fix the name of the libraries, and add the AArch64 utils library.
Link clang against the AArch64 libraries.
Build libllvmaarch64utils
Add the AArch64 target
Add the minimal library files needed to build/install includes
Allow xlint to be built
Add an openssl config header for arm64 so we can build a toolchain
Add an empty _setjmp and _longjmp for libstand.
Add the arm64 bits to ficl
Add the machine headers to build ficl.
Add ELF related defines needed by loader
Teach clang about FreeBSD running on AArch64
Add efi_handle_any to allow us to get a 'current' device when we lack a
driver for the boot device, e.g. when loading the loader over semihosting.
Add the arm64 version of efibind.h
Add the arm64 bits to build an efi loader.

We can't use objcopy to build the efi header in assembly, then use objcopy
to create a 'binary' file with this header at the start.
Remove an unneeded setenv and add more EFI commands
Add a filesystem to read using the EFI Simple Filesystem Protocol.
Define DEVT_FS. this should have been included in r261923.
Build the required elf64 files on arm64.
We have a filesystem when using a loader from semihosting. There is no need
to use the first found device anymore.