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>

pkgs/development/libraries/capnproto/default.nix

@@ -0,0 +1,39 @@
+{ lib
+, stdenv
+, fetchFromGitHub
+, capnproto
+, cmake }:
+
+stdenv.mkDerivation rec {
+  pname = "capnproto";
+  version = "0.9.1";
+
+  # release tarballs are missing some ekam rules
+  src = fetchFromGitHub {
+    owner = "capnproto";
+    repo = "capnproto";
+    rev = "v${version}";
+    sha256 = "0cbiwkmd29abih8rjjm35dfkrkr8c6axbzq3fkryay6jyvpi42c5";
+  };
+
+  nativeBuildInputs = [ cmake ]
+    ++ lib.optional (!(stdenv.buildPlatform.canExecute stdenv.hostPlatform)) capnproto;
+
+  cmakeFlags = lib.optional (!(stdenv.buildPlatform.canExecute stdenv.hostPlatform)) "-DEXTERNAL_CAPNP";
+
+  # Upstream 77ac9154440bcc216fda1092fd5bb51da62ae09c, modified to apply to v0.9.1.  Drop on update.
+  patches = lib.optional stdenv.hostPlatform.isMusl ./musl-no-fibers.patch;
+
+  meta = with lib; {
+    homepage    = "https://capnproto.org/";
+    description = "Cap'n Proto cerealization protocol";
+    longDescription = ''
+      Cap’n Proto is an insanely fast data interchange format and
+      capability-based RPC system. Think JSON, except binary. Or think Protocol
+      Buffers, except faster.
+    '';
+    license     = licenses.mit;
+    platforms   = platforms.all;
+    maintainers = with maintainers; [ cstrahan ];
+  };
+}