perf/x86/amd/ibs: Convert force_ibs_eilvt_setup() to void

perf/x86/amd/ibs: Convert force_ibs_eilvt_setup() to void

The caller of force_ibs_eilvt_setup() is ibs_eilvt_setup()
which does not care about the return values.

So mark it void and clean up the return statements.

Signed-off-by: Aravind Gopalakrishnan <aravind.gopalakrishnan@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <hpa@zytor.com>
Cc: <paulus@samba.org>
Cc: <tglx@linutronix.de>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1422037175-20957-1-git-send-email-aravind.gopalakrishnan@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>