boost177: use fetchpatch's `relative` argument

We can drop `includes` since there's only one file in that directory.

pkgs/development/libraries/boost/generic.nix

@@ -130,10 +130,8 @@ stdenv.mkDerivation {
   ++ optional (versionAtLeast version "1.73") ./cmake-paths-173.patch
   ++ optional (version == "1.77.0") (fetchpatch {
     url = "https://github.com/boostorg/math/commit/7d482f6ebc356e6ec455ccb5f51a23971bf6ce5b.patch";
+    relative = "include";
     sha256 = "sha256-KlmIbixcds6GyKYt1fx5BxDIrU7msrgDdYo9Va/KJR4=";
-    stripLen = 2;
-    extraPrefix = "";
-    includes = [ "boost/math/special_functions/detail/bernoulli_details.hpp" ];
   });
 
   meta = {