podman: workaround for macOS 11 and below

See https://trac.macports.org/ticket/69683
See crc-org/vfkit#125

sysutils/podman/Portfile

@@ -9,6 +9,7 @@ PortGroup           golang 1.0
 go.setup            github.com/containers/podman 5.0.1 v
 github.tarball_from archive
 revision            0
+epoch               0
 
 categories          sysutils
 license             Apache-2
@@ -47,6 +48,26 @@ build.args          PYTHON=${prefix}/bin/python${py_ver} \
                     PRE_COMMIT=${prefix}/bin/pre-commit
 build.target        ${name}-remote ${name}-mac-helper docs
 
+if {${os.platform} eq "darwin" && ${os.major} <= 20} {
+    # See https://trac.macports.org/ticket/69578
+    go.setup            github.com/containers/podman 4.9.3 v
+    epoch               1
+
+    checksums           ${distname}${extract.suffix} \
+                         rmd160  dd87729822e5486c174815445e814546b3a7e98b \
+                         sha256  37afc5bba2738c68dc24400893b99226c658cc9a2b22309f4d7abe7225d8c437 \
+                         size    21727849
+
+    depends_run-delete   port:vfkit
+
+    notes-append "
+    WARN: Currently using podman 4.9.3 instead of 5.0.0+. See the reasons:
+    https://trac.macports.org/ticket/69683
+
+    ***
+    "
+}
+
 destroot {
     xinstall -m 0755 ${worksrcpath}/bin/darwin/${name} \
         ${destroot}${prefix}/bin/
@@ -71,7 +92,7 @@ destroot {
         ${destroot}${prefix}/share/fish/vendor_completions.d/
 }
 
-notes "
+notes-append "
 If you have an issue where podman won't run on ARM then try the following:
 
 https://trac.macports.org/ticket/67731#comment:14