nand: mxc: Switch NAND SPL to generic SPL

This also fixes support for mx31pdk and tx25, which had been broken by commit
e05e5de7fae5bec79617e113916dac6631251156.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Acked-by: Scott Wood <scottwood@freescale.com>
Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
index c77c0c4..bcb7161 100644
--- a/drivers/mtd/nand/Makefile
+++ b/drivers/mtd/nand/Makefile
@@ -82,6 +82,7 @@
 else  # minimal SPL drivers
 
 COBJS-$(CONFIG_NAND_FSL_ELBC) += fsl_elbc_spl.o
+COBJS-$(CONFIG_NAND_MXC) += mxc_nand_spl.o
 
 endif # drivers
 endif # nand