mhi: core: reduce logging level for errors msg during queue transfer

"MHI not in active state..." is not a fatal error message, this
happens when MHI is in process of shutdown, but some clients
not yet receive shutdown notification.

CRs-Fixed: 2261930
Change-Id: I5732a6348d17f860b43873602706632aa065bdda
Signed-off-by: Sujeev Dias <sdias@codeaurora.org>