ftrace/x86: Update i386 call to prepare_ftrace_return()

ftrace/x86: Update i386 call to prepare_ftrace_return()

The parameters for prepare_ftrace_return() used by the function graph
tracer were swapped to simplify the code on x86_64. But i386 function
graph trampoline also calls this function, and it did not have its
parameters swapped.

Link: http://lkml.kernel.org/r/20141210231732.GA24163@wfg-t540p.sh.intel.com
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Tested-by: Fengguang Wu <fengguang.wu@intel.com>
Fixes: 6a06bdbf7f9c "ftrace/fgraph/x86: Have prepare_ftrace_return() take ip as first parameter"
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>