blk-mq: handle failure path for initializing hctx
blk-mq: handle failure path for initializing hctx

Failure of initializing one hctx isn't handled, so this patch
introduces blk_mq_init_hctx() and its pair to handle it explicitly.
Also this patch makes code cleaner.

Reviewed-by: Christoph Hellwig <923f7720577207a44b32e59bbfbea59d27f1ae8e@lst.de>
Signed-off-by: Ming Lei <8d0fc11caeb4659419f0ba3104eb4a9d30848d42@canonical.com>
Signed-off-by: Jens Axboe <cd8c6775e60d6f67a6984377324e5290df3d5358@fb.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs