Update arm64fx MEM groups bandwidth metrics
Created by: breiters
Metrics and correction terms taken from the fujitsu a64fx microarchitectural manual v1.4 page 85 and the a64fx pmu events errata v1.0.
L2D_CACHE_REFILL (corrected) = L2D_CACHE_REFILL - L2D_SWAP_DM - L2D_CACHE_MIBMCH_PRF
Bandwidth (corrected) = (L2D_CACHE_REFILL - (L2D_SWAP_DM + L2D_CACHE_MIBMCH_PRF) + L2D_CACHE_WB) * 256 / time