Changeset 11372:60739171853b

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arm,dev,config: always preent the PMU but add option to enable
Always attach the PMU to an ARM core but do not enable the

relevant instructions/events unless asked for by setting the

new command line option --pmu.
Note: this should work fine for 1 core systems, for multi-core

there might be an interrupt delivery issue still (SPI vs. PPI).

Consider this as an example for people who want to work on it

as the question has previously come up on the mailing lists on

how to hook this up.