arm64: pmu: Wire-up Cortex A53 L2 cache events and DTLB refills

Add missing L2 cache events: read/write accesses and misses, as well as
the DTLB refills.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>