fix(pmu): extend PMEVTYPER.evtCount width

FEAT_PMUv3p1 extends this field from 10 to 16 bits. The upper bits are
RES0 so backwards compatibility is preserved

Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
Change-Id: I98abb14bfe8e72f99318fe7d3e26420d91c1c55a
1 file changed