msm: ipa: Only attach to the IOMMU after setting all domain attrs

Attaching an IOMMU domain to an IOMMU device should only be done after
setting all relevant domain attributes on the domain, but we're
currently attaching before setting an important attribute.  Fix this.

Change-Id: Ife8ec2090060d99334d97e39b5cb1ea67d8b59bf
Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org>