feat: update vendored xz to 5.6.1 #50

	name: Linux x86
	on: [push, pull_request]
	jobs:
	FullCompile:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	cCompiler: [ "clang", "gcc" ]
	steps:
	- name: Install Go
	uses: actions/setup-go@v2
	with:
	go-version: 1.16.x
	- name: Checkout code
	uses: actions/checkout@v2
	- name: Retrieve submodule
	run: git submodule update --init
	- name: Build
	run: CC=${{ matrix.cCompiler }} go build internal/goxz/goxz.go
	- name: Test
	run: CC=${{ matrix.cCompiler }} go test ./...

	PrecompiledLZMA:
	runs-on: ubuntu-latest
	steps:
	- name: Install Go
	uses: actions/setup-go@v2
	with:
	go-version: 1.16.x
	- name: Checkout code
	uses: actions/checkout@v2
	- name: Retrieve submodule
	run: git submodule update --init
	- name: Build
	run: CGO_CFLAGS=-DGOXZ_SKIP_C_COMPILATION CGO_LDFLAGS=-llzma go build internal/goxz/goxz.go
	- name: Test
	run: CGO_CFLAGS=-DGOXZ_SKIP_C_COMPILATION CGO_LDFLAGS=-llzma go test ./...

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