pinctrl: imx: Define imx6_pinctrl_soc_info in .data section

pinctrl: imx: Define imx6_pinctrl_soc_info in .data section

This commit is necessary to be able to re-use the pinctrl code in early
SPL to properly configure pins.

The problem is that those "static" structures (without explicit
initialization) are placed in the SDRAM area, which corresponds to
u-boot proper (not even SPL).
Hence, when one wants to configure pins before relocation via DTS/DM,
the board hangs (imx6q SoC powered one) as only OCRAM area is available
(0x009xxxxx).

This commit prevents from this issue by moving the imx6_pinctrl_soc_info
structure to data section (from BSS).

Signed-off-by: Lukasz Majewski <lukma@denx.de>
Reviewed-by: Peng Fan <peng.fan@nxp.com>