usb: mon: replace %p with %pK

Format specifier %p can leak kernel addresses while not valuing the
kptr_restrict system settings. When kptr_restrict is set to (1), kernel
pointers printed using the %pK format specifier will be replaced with
Zeros. Debugging Note: &pK prints only Zeros as address. If you need
actual address information, write 0 to kptr_restrict.

echo 0 > /proc/sys/kernel/kptr_restrict

Change-Id: I4d65692f26e9c26dde98a80bb81f134225abaf16
Signed-off-by: Vamsi Krishna Samavedam <vskrishn@codeaurora.org>