arm: dts: msm8226: reduce current limit to 400mA.

As per the power-grid the max. current that can be drawn is
400mA. Previously the card was drawing more than this since
it was being advertised as 800mA. This change applies to QRD
alone now, since other variants have not been tested yet.

CRs-fixed: 470661
Change-Id: Ib10cc98e462edfb71d23e5763d403466dcb4086f
Signed-off-by: Asutosh Das <asutoshd@codeaurora.org>