Moved most of the implementation of CALL32_CBClient(Ex) to the C
code.

dlls/kernel/kernel16_private.h

diff --git a/dlls/kernel/kernel16_private.h b/dlls/kernel/kernel16_private.h
index 2437828..a28ea17 100644
--- a/dlls/kernel/kernel16_private.h
+++ b/dlls/kernel/kernel16_private.h
@@ -224,4 +224,7 @@
 extern TDB *TASK_GetCurrent(void);
 extern void TASK_InstallTHHook( THHOOK *pNewThook );
 
+extern SEGPTR CALL32_CBClient_RetAddr;
+extern SEGPTR CALL32_CBClientEx_RetAddr;
+
 #endif  /* __WINE_KERNEL16_PRIVATE_H */