ARM: SPL: Move gpmc_init() to spl_board_init()

This is an OMAP/related-specific function, move calling it to
spl_board_init() and turn on CONFIG_SPL_BOARD_INIT on the boards that
enabled NAND and didn't enable this already.

Signed-off-by: Tom Rini <trini@ti.com>
diff --git a/arch/arm/cpu/armv7/omap3/board.c b/arch/arm/cpu/armv7/omap3/board.c
index 3d74f09..52196c8 100644
--- a/arch/arm/cpu/armv7/omap3/board.c
+++ b/arch/arm/cpu/armv7/omap3/board.c
@@ -106,6 +106,9 @@
 
 void spl_board_init(void)
 {
+#ifdef CONFIG_SPL_NAND_SUPPORT
+	gpmc_init();
+#endif
 #ifdef CONFIG_SPL_I2C_SUPPORT
 	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
 #endif