kfence: report sensitive information based on no_hash_pointers

We cannot rely on CONFIG_DEBUG_KERNEL to decide if we're running a "debug
kernel" where we can safely show potentially sensitive information in the
kernel log.

Instead, simply rely on the newly introduced "no_hash_pointers" to print
unhashed kernel pointers, as well as decide if our reports can include
other potentially sensitive information such as registers and corrupted
bytes.

Link: https://lkml.kernel.org/r/20210223082043.1972742-1-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Cc: Timur Tabi <timur@kernel.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>