accel/qaic: Free user handle on interrupted mutex

After user handle is allocated, if mutex is interrupted, we do not free
the user handle and return an error. Kref had been initialized, but not
added to users list, so device teardown would also not call free_usr.

Fixes: c501ca23

 ("accel/qaic: Add uapi and core driver file")
Signed-off-by: Carl Vanderlip <quic_carlv@quicinc.com>
Reviewed-by: Pranjal Ramajor Asha Kanojiya <quic_pkanojiy@quicinc.com>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Signed-off-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230602210440.8411-2-quic_jhugo@quicinc.com