Check CONFIG_FREEZER instead of CONFIG_PM because kprobe booster
depends on freeze_processes() and thaw_processes() when CONFIG_PREEMPT=y.

This fixes a linkage error which occurs when CONFIG_PREEMPT=y, CONFIG_PM=y
and CONFIG_FREEZER=n.
Reported-by: NCheng Renquan <crquan@gmail.com>
Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NLen Brown <len.brown@intel.com>