[gtk-osx] Fix error in automatically setting sdk_version.

[John Ralls <jralls src gnome org>]

commit 3f755ee14b33746f87c639e5a5ca7dd5ffed9720
Author: John Ralls <jralls ceridwen us>
Date:   Thu Feb 27 08:59:12 2014 -0800

    Fix error in automatically setting sdk_version.

 jhbuildrc-gtk-osx |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/jhbuildrc-gtk-osx b/jhbuildrc-gtk-osx
index 2c93854..ebb3509 100644
--- a/jhbuildrc-gtk-osx
+++ b/jhbuildrc-gtk-osx
@@ -242,7 +242,7 @@ def setup_sdk(target, sdk_version, architectures=[_default_arch]):
 
 #OSX 10.9 doesn't have /usr/include, so we need to set the sdkdir to XCode.app:
     if sdk_version == 'native' and _osx_version >= 9.0:
-        sdk_version = str(10 + _osx_version / 10)
+        sdk_version = '10.' + str(int(_osx_version))
 
     _toolpath = os.path.join("/usr", "bin")
     if xcodepath: