Revert "oprofile: discover counters for op ppro too"

This reverts commit 59512900.

arch_perfmon_setup_counters() is actually never called for ppro, so
there is no code that changes the numbers in op_ppro_spec. The patch
as it is has no effect.

Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>