powerpc/64/interrupt: add missing kprobe annotations on interrupt exit symbols

If one interrupt exit symbol must not be kprobed, none of them can be,
without more justification for why it's safe. Disallow kprobing on any
of the (non-local) labels in the exit paths.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210630074621.2109197-8-npiggin@gmail.com