ARM: dts: msm: Add valid-check property for msmthorium

Add property qcom,valid-status-check property to check
the valid bit in the status register when reading
the ADC data. If the valid bit is not set proceed to
read the data register again.

Change-Id: I5ec119fd263edcdba7ba0dce8b443e0256ecf350
Signed-off-by: Rama Krishna Phani A <rphani@codeaurora.org>