smp + block-mq: Update the block-mq patches.

This is an all-in-one updating the block-mq related patches. It replaces
current patches with the following patches staged for upstream:

   71425189 ("blk-mq: Don't complete on a remote CPU in force threaded mode")
   66040b2d ("smp: Process pending softirqs in flush_smp_call_function_from_idle()")
   0a2efafb ("blk-mq: Always complete remote completions requests in softirq")
   f9ab4918 ("blk-mq: Use llist_head for blk_cpu_done")

plus one patch posted to the list:

   smp: Wake ksoftirqd on PREEMPT_RT instead do_softirq().
   https://lkml.kernel.org/r/20210215181027.mxkzolp3fibfiwvv@linutronix.de



Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>