zig: add new package at v0.7.1 (#22046)

etc/spack/defaults/packages.yaml

@@ -50,6 +50,7 @@ packages:
       yacc: [bison, byacc]
       flame: [libflame, amdlibflame]
       uuid: [util-linux-uuid, libuuid]
+      ziglang: [zig]
     permissions:
       read: world
       write: user

var/spack/repos/builtin/packages/zig/package.py

@@ -0,0 +1,22 @@
+# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+# Spack Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+class Zig(CMakePackage):
+    """A general-purpose programming language and toolchain for maintaining
+    robust, optimal, and reusable software.
+    """
+
+    homepage = "https://ziglang.org/"
+    git = "https://github.com/ziglang/zig.git"
+
+    version('0.7.1', tag='0.7.1')
+
+    variant(
+        'build_type', values=('Release', 'RelWithDebInfo', 'MinSizeRel'),
+        default='Release', description='CMake build type'
+    )
+
+    depends_on('llvm@11.0.0: +all_targets')
+
+    provides('ziglang')