perf, arch: Cleanup perf-pmu init vs lockup-detector

The perf hardware pmu got initialized at various points in the boot,
some before early_initcall() some after (notably arch_initcall).

The problem is that the NMI lockup detector is ran from early_initcall()
and expects the hardware pmu to be present.

Sanitize this by moving all architecture hardware pmu implementations to
initialize at early_initcall() and move the lockup detector to an explicit
initcall right after that.

Cc: paulus <paulus@samba.org>
Cc: davem <davem@davemloft.net>
Cc: Michael Cree <mcree@orcon.net.nz>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1290707759.2145.119.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 2c79e92..d2e63d1 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -316,6 +316,7 @@
 				  size_t *lenp, loff_t *ppos);
 extern unsigned int  softlockup_panic;
 extern int softlockup_thresh;
+void lockup_detector_init(void);
 #else
 static inline void touch_softlockup_watchdog(void)
 {
@@ -326,6 +327,9 @@
 static inline void touch_all_softlockup_watchdogs(void)
 {
 }
+static inline void lockup_detector_init(void)
+{
+}
 #endif
 
 #ifdef CONFIG_DETECT_HUNG_TASK