Fuchsia support

For information about checking out and building Fuchsia see Getting Started and Soure Code. Image needs to be configured with sshd support:

fx set x64 --packages garnet/packages/products/sshd
fx full-build

To update descriptions run:

make extract TARGETOS=fuchsia SOURCEDIR=/path/to/fuchsia/checkout
make generate

To build binaries:

make TARGETOS=fuchsia TARGETARCH=amd64 SOURCEDIR=/path/to/fuchsia/checkout

Run syz-manager with a config along the lines of:

	"name": "fuchsia",
	"target": "fuchsia/amd64",
	"http": ":12345",
	"workdir": "/workdir.fuchsia",
	"kernel_obj": "/fuchsia/out/build-zircon/build-x64",
	"syzkaller": "/syzkaller",
	"image": "/fuchsia/out/x64/images/fvm.blk",
	"sshkey": "/fuchsia/out/x64/ssh-keys/id_ed25519",
	"reproduce": false,
	"cover": false,
	"procs": 8,
	"type": "qemu",
	"vm": {
		"count": 10,
		"cpu": 4,
		"mem": 2048,
		"kernel": "/fuchsia/out/build-zircon/build-x64/zircon.bin",
		"initrd": "/fuchsia/out/x64/bootdata-blob.bin"