sh: Provide CALLER_ADDRx definitions even when ftrace is disabled.

Despite being located in the ftrace header, the CALLER_ADDRx definitions
are used by generic code. As such, we have to provide it generically, and
given that there is no real dependence on ftrace in the first place, the
definitions can just be moved out.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>