arm_pmu: Use of_cpu_node_to_id helper

Use the new generic helper, of_cpu_node_to_id(), to map a
a phandle to the logical CPU number while parsing the
PMU irq affinity.

Change-Id: Iec4e1d032715838b5a468e1e4de417b72038bb7d
Cc: Will Deacon <will.deacon@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Git-commit: 66582787314ed0bd1dcac3f7a2b98ff71f3fb653
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


Signed-off-by: Raghavendra Rao Ananta <rananta@codeaurora.org>