sstate: explicitly name the checkhashes thread pool

Give this thread pool a name for clarity.

(From OE-Core rev: 57ea50fcfe81f47b93b9302d1aab2e81dcdd3105)

Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/classes/sstate.bbclass

@@ -1014,7 +1014,8 @@ def sstate_checkhashes(sq_data, d, siginfo=False, currentcount=0, summary=True,
 
             bb.event.enable_threadlock()
             pool = oe.utils.ThreadedPool(nproc, len(tasklist),
-                    worker_init=checkstatus_init, worker_end=checkstatus_end)
+                    worker_init=checkstatus_init, worker_end=checkstatus_end,
+                    name="sstate_checkhashes-")
             for t in tasklist:
                 pool.add_task(checkstatus, t)
             pool.start()