powerpc/pseries: move hcall_tracepoint_refcount out of .toc

The .toc section is not really intended for arbitrary data. Writable
data in particular prevents making the TOC read-only after relocation.
Move hcall_tracepoint_refcount into the .data section.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220926053823.2668799-1-npiggin@gmail.com