perf tools: Fix a compiler warning of NULL pointer

A compiler warning on the second argument of bsearch() should not be
NULL, but there's a case we might pass it.  Let's return early if we
don't have any DSOs to search in __dsos__find_by_longname_id().

  util/dsos.c:184:8: runtime error: null pointer passed as argument 2, which is declared to never be null

Reported-by: kernel test robot <[email protected]>
Reviewed-by: Kan Liang <[email protected]>
Closes: https://lore.kernel.org/oe-lkp/[email protected]
Signed-off-by: Namhyung Kim <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

0 files changed, 0 insertions, 0 deletions