ARM: dts: msm: Re-add Q6 SMEM size entry on sdxpoorwills

Re-add "qcom,ipa-q6-smem-size" entry to configure SMEM
partition according to the specified  size.

Change-Id: Ifef322058c31dd5f8e3ad05aecb1ee1fe1118d80
CRs-fixed: 2219398
Signed-off-by: Michael Adisumarta <madisuma@codeaurora.org>