This change is required after the e6500 perf support has been added.
There are 6 counters in e6500 core instead of 4 in e500 core and
the MAX_HWEVENTS counter should be changed accordingly from 4 to 6.
Added also runtime check for counters overflow.
Signed-off-by: NCatalin Udma <catalin.udma@freescale.com>
Signed-off-by: NLijun Pan <Lijun.Pan@freescale.com>
Signed-off-by: NScott Wood <scottwood@freescale.com>