ARM: dts: imx6: Add imx-weim parameters to dtsi's

imx-weim should always set address-cells to 2,
and size_cells to 1.
On imx6, fsl,weim-cs-gpr will always be &gpr

Set these common parameters in the dtsi file,
rather than in a downstream dts.

Signed-off-by: Joshua Clayton <stillcompiling@gmail.com>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>