percpu: stop printing kernel addresses

Since commit ad67b74d ("printk: hash addresses printed with %p"),
at boot "____ptrval____" is printed instead of actual addresses:

    percpu: Embedded 38 pages/cpu @(____ptrval____) s124376 r0 d31272 u524288

Instead of changing the print to "%px", and leaking kernel addresses,
just remove the print completely, cfr. e.g. commit 071929db
("arm64: Stop printing the virtual memory layout").

Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: Dennis Zhou <dennis@kernel.org>