Add a ranges; line to the tscadc node. This creates a 1:1 mapping between
the addresses used by tscadc and those in its child nodes (adc, tsc).

Without such a mapping, the reg = ... lines in the tsc and adc nodes do
not create a resource. Probing the fsl-imx25-tcq and fsl-imx25-tsadc
drivers will then fail since there's no IORESOURCE_MEM.
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Fixes: 92f651f3 ("ARM: dts: imx25: Add TSC and ADC support")
Signed-off-by: Shawn Guo <shawnguo@kernel.org>