Move I2C driver model init earlier in the boot sequence

Move I2C driver model init earlier in the boot sequence

This avoids oopsing in statically linked systems when some
subsystems register I2C drivers in subsys_initcall() code,
but those subsystems are linked (and initialized) before I2C.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>