arm: dma-mapping: don't attach the clients to smmu device by default

When SMMU master call arch_setup_dma_ops after SMMU initialization, it
tries to attach a CB to this device. And later, the same master tries to
create mapping and attach a CB to the same device as part of their code.
Avoid this.
This is aligned to the 64bit implementation.

Change-Id: I880e74919236658570cf84bac04d52d4ffd997e3
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>