Fixed the patches search path.

my-packages/my-games.scm

@@ -205,7 +205,10 @@ strife, chex quest, and fan-created games like harmony, hacx and freedoom.")
       (base32 "0arfx7f2rfgc68ph4sq99hjrjjqsxiq6s4ppv0swyaqhqm0g2hrz"))
      ;; Fix textures for SDL 2.0.14.
      ;; See <https://github.com/TurningWheel/Barony/pull/582>.
-     (patches (search-patches "barony-fix-make-install-script.patch"))))
+     (patches (search-path
+               (map (cut string-append <> "/my-packages/patches")
+                    %load-path)
+               "barony-fix-make-install-script.patch"))))
    (build-system cmake-build-system)
    (arguments
     '(#:configure-flags