oprofile, x86: Remove duplicate check for IBS_CAPS_OPCNT

Since oprofile is setting up ibs_op/dispatched_ops in the fs only if
the feature is available, its corresponding variable
ibs_config.dispatched_ops is only set, if the feature is
available. Thus the check is duplicate and can be removed.

Signed-off-by: Robert Richter <robert.richter@amd.com>