uboot: (firmwareOdroidC2/C4) don't invoke patch tool, use patches = [] instead

https://github.com/NixOS/nixpkgs/blob/master/pkgs/stdenv/generic/setup.sh#L948
this can do it nicely.

Signed-off-by: Anton Arapov <anton@deadbeef.mx>

nixos/tests/pam/test_chfn.py

@@ -0,0 +1,27 @@
+expected_lines = {
+    "account required pam_unix.so",
+    "account sufficient @@pam_krb5@@/lib/security/pam_krb5.so",
+    "auth [default=die success=done] @@pam_ccreds@@/lib/security/pam_ccreds.so action=validate use_first_pass",
+    "auth [default=ignore success=1 service_err=reset] @@pam_krb5@@/lib/security/pam_krb5.so use_first_pass",
+    "auth required pam_deny.so",
+    "auth sufficient @@pam_ccreds@@/lib/security/pam_ccreds.so action=store use_first_pass",
+    "auth sufficient pam_rootok.so",
+    "auth sufficient pam_unix.so   likeauth try_first_pass",
+    "password sufficient @@pam_krb5@@/lib/security/pam_krb5.so use_first_pass",
+    "password sufficient pam_unix.so nullok sha512",
+    "session optional @@pam_krb5@@/lib/security/pam_krb5.so",
+    "session required pam_env.so conffile=/etc/pam/environment readenv=0",
+    "session required pam_unix.so",
+}
+actual_lines = set(machine.succeed("cat /etc/pam.d/chfn").splitlines())
+
+missing_lines = expected_lines - actual_lines
+extra_lines = actual_lines - expected_lines
+non_functional_lines = set([line for line in extra_lines if (line == "" or line.startswith("#"))])
+unexpected_functional_lines = extra_lines - non_functional_lines
+
+with subtest("All expected lines are in the file"):
+    assert not missing_lines, f"Missing lines: {missing_lines}"
+
+with subtest("All remaining lines are empty or comments"):
+    assert not unexpected_functional_lines, f"Unexpected lines: {unexpected_functional_lines}"