To enable presenting of Performance Monitor Counter Registers (PMC1 to
PMC6) as part of extended regsiters, this patch adds these to
sample_reg_mask in the tool side (to use with -I? option).

Simplified the PERF_REG_PMU_MASK_300/31 definition. Excluded the
unsupported SPRs (MMCR3, SIER2, SIER3) from extended mask value for
CPU_FTR_ARCH_300.
Signed-off-by: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>