perf_counter: powerpc: Fix two compile warnings

perf_counter: powerpc: Fix two compile warnings

This fixes a couple of compile warnings that crept into the powerpc
perf_counter code recently:

   CC      arch/powerpc/kernel/perf_counter.o
 arch/powerpc/kernel/perf_counter.c: In function 'record_and_restart':
 arch/powerpc/kernel/perf_counter.c:1016: warning: unused variable 'addr'
 arch/powerpc/kernel/perf_counter.c: In function 'hw_perf_counter_init':
 arch/powerpc/kernel/perf_counter.c:891: warning: 'ev' may be used uninitialized in this function

Stephen Rothwell reported this against linux-next as well.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <18998.12884.787039.22202@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>