Update -help to list correct paths searched within PPROF_BINARY_PATH. (#355)
Update -help to list correct paths searched within PPROF_BINARY_PATH. (#355)

The code was updated in #335 but the doc wasn't updated. Also the doc
didn't include $path which is searched as well, see locateBinaries in
internal/driver/fetch.go.
google/pprof,rauls5382/pprof,google/pprof,google/pprof,rauls5382/pprof,google/pprof