pinctrl: imx6ul: Fix pinctrl data overlapped with DT area

before relocation pinctrl data BSS is overlapping DT area,
when .data is using uninitialized global variable,
imx6_pinctrl_soc_info. So assign them flags ZERO_OFFSET_VALID
to prevent BSS overlap

Suggested-by: Lokesh Vutla <lokeshvutla@ti.com>
Reported-by: Jagan Teki <jagan@amarulasolutions.com>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>