orca: add 6.0.0 avx2 version (spack#45824)

The avx2 version can be downloaded from the ORCA [forum](https://orcaforum.kofo.mpg.de/app.php/dlext/?view=detail&df_id=214#).

The version is named `avx2-6.0.0` (as opposed to the more
natural-looking `6.0.0-avx2`) to avoid the avx2 version shadowing the
non-avx2 one. Definitely open for better suggestion.

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

@@ -23,6 +23,9 @@ class Orca(Package):
 
     license("LGPL-2.1-or-later")
 
+    version(
+        "avx2-6.0.0", sha256="02c21294efe7b1b721e26cb90f98ee15ad682d02807201b7d217dfe67905a2fd"
+    )
     version("6.0.0", sha256="219bd1deb6d64a63cb72471926cb81665cbbcdec19f9c9549761be67d49a29c6")
     version("5.0.4", sha256="c4ea5aea60da7bcb18a6b7042609206fbeb2a765c6fa958c5689d450b588b036")
     version("5.0.3", sha256="b8b9076d1711150a6d6cb3eb30b18e2782fa847c5a86d8404b9339faef105043")
@@ -40,17 +43,22 @@ class Orca(Package):
         "5.0.3": "4.1.2",
         "5.0.4": "4.1.2",
         "6.0.0": "4.1.6",
+        "avx2-6.0.0": "4.1.6",
     }
     for orca_version, openmpi_version in openmpi_versions.items():
         depends_on(
             "openmpi@{0}".format(openmpi_version), type="run", when="@{0}".format(orca_version)
         )
 
     def url_for_version(self, version):
-        openmpi_version = self.openmpi_versions[str(version.dotted)].replace(".", "")
+        openmpi_version = self.openmpi_versions[version.string].replace(".", "")
         if openmpi_version == "412":
             openmpi_version = "411"
-        return f"file://{os.getcwd()}/orca_{version.underscored}_linux_x86-64_shared_openmpi{openmpi_version}.tar.xz"
+        ver_parts = version.string.split("-")
+        ver_underscored = ver_parts[-1].replace(".", "_")
+        features = ver_parts[:-1] + ["shared"]
+        feature_text = "_".join(features)
+        return f"file://{os.getcwd()}/orca_{ver_underscored}_linux_x86-64_{feature_text}_openmpi{openmpi_version}.tar.xz"
 
     def install(self, spec, prefix):
         mkdirp(prefix.bin)