MFC r356730: storvsc: properly set residual data length on errors

This change is based on Linux commit 40630f462824ee. csio.resid should
account for transfer_len only for success and SRB_STATUS_DATA_OVERRUN
condition.

I am not sure how exactly this change works, but I have a report from a
user that they see lots of checksum errors when running a pool scrub
concurrently with iozone -l 1 -s 100G. After applying this patch the
problem cannot be reproduced.

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