dm: sunxi: sata: Don't build sata support into SPL

This is not used in SPL so we do not need to compile it. Make this change
before adding driver-model support to the driver, to avoid build errors.
With driver model we define a U_BOOT_DRIVER() which would otherwise be
present in SPL and not be garbage-collected when building.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>

board/sunxi/Makefile

@@ -10,7 +10,9 @@
 #
 obj-y	+= board.o
 obj-$(CONFIG_SUNXI_GMAC)	+= gmac.o
+ifndef CONFIG_SPL_BUILD
 obj-$(CONFIG_SUNXI_AHCI)	+= ahci.o
+endif
 obj-$(CONFIG_MACH_SUN4I)	+= dram_sun4i_auto.o
 obj-$(CONFIG_MACH_SUN5I)	+= dram_sun5i_auto.o
 obj-$(CONFIG_MACH_SUN7I)	+= dram_sun5i_auto.o