db-*: only use the osx.patch for db5 where it applies

This unbreaks builds of all other versions (4.* and 6.*).

pkgs/development/libraries/db/db-5.3.nix

@@ -3,4 +3,5 @@
 import ./generic.nix (args // rec {
   version = "5.3.28";
   sha256 = "0a1n5hbl7027fbz5lm0vp0zzfp1hmxnz14wx3zl9563h83br5ag0";
+  extraPatches = [ ./osx.patch ];
 })

pkgs/development/libraries/db/generic.nix

@@ -18,10 +18,6 @@ stdenv.mkDerivation rec {
 
   patches = extraPatches;
 
-  patchPhase = ''
-    patch src/dbinc/atomic.h < ${./osx.patch}
-  '';
-
   configureFlags = [
     (if cxxSupport then "--enable-cxx" else "--disable-cxx")
     (if compat185 then "--enable-compat185" else "--disable-compat185")

pkgs/development/libraries/db/osx.patch

@@ -1,5 +1,5 @@
---- src/dbinc/atomic.h	2013-03-12 14:07:22.000000000 -0400
-+++ src/dbinc/atomic.h.change	2013-03-12 14:06:35.000000000 -0400
+--- a/src/dbinc/atomic.h	2013-03-12 14:07:22.000000000 -0400
++++ b/src/dbinc/atomic.h.change	2013-03-12 14:06:35.000000000 -0400
 @@ -144,7 +144,7 @@
  #define	atomic_inc(env, p)	__atomic_inc(p)
  #define	atomic_dec(env, p)	__atomic_dec(p)