BACKPORT: docs: correct documentation for %pK

Current documentation indicates that %pK prints a leading '0x'. This is
not the case.

Correct documentation for printk specifier %pK.

Signed-off-by: Tobin C. Harding <me@tobin.cc>
(cherry picked from commit 553d8e8b107159088cc4e2855a2bd9a358365e3f)
Signed-off-by: Sandeep Patil <sspatil@android.com>

Bug: 78533979
Test: Builds
Change-Id: I69439ea6aca65d209c43b4cc54ead7d2df9af5c1