perf evsel: Fix incorrect handling of type _TERM_DRV_CFG

perf evsel: Fix incorrect handling of type _TERM_DRV_CFG

Commit ("d0565132605f perf evsel: Enable type checking for
perf_evsel_config_term types") assumes PERF_EVSEL__CONFIG_TERM_DRV_CFG
isn't used and as such adds a BUG_ON().

Since the enumeration type is used in macro ADD_CONFIG_TERM() the change
break CoreSight trace acquisition.

This patch restores the original code.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: d0565132605f ("perf evsel: Enable type checking for perf_evsel_config_term types")
Link: http://lkml.kernel.org/r/1515617211-32024-1-git-send-email-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>