doc: move kernel_v2 to kernel

Change-Id: I6caa94bc1a3d1986966652cd0a24bf22f3697481
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
diff --git a/doc/api/kernel_api.rst b/doc/api/kernel_api.rst
index 7af05bc..1576680 100644
--- a/doc/api/kernel_api.rst
+++ b/doc/api/kernel_api.rst
@@ -4,7 +4,7 @@
 ###########
 
 This section contains APIs for the kernel's core services,
-as described in the :ref:`kernel_v2`.
+as described in the :ref:`kernel`.
 
 .. important::
     Unless otherwise noted these APIs can be used by threads, but not by ISRs.