linux-phytec-fsl

sh64: Ensure KALLSYMS is enabled for unwinder use.

Since sh64 depends on kallsyms unconditionally for its stack unwinding to
be of any use, make sure it's selected. In practice we don't have any
case where it's disabled anyways, so moving to this to a select is fine.

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