stm32mp1: Add UBIFS boot capability

Add support for boot from NAND in generic ditribution command.

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
diff --git a/include/configs/stm32mp1.h b/include/configs/stm32mp1.h
index 1c05ccb..24f7b9d 100644
--- a/include/configs/stm32mp1.h
+++ b/include/configs/stm32mp1.h
@@ -95,6 +95,7 @@
 
 #define BOOT_TARGET_DEVICES(func) \
 	func(MMC, mmc, 1) \
+	func(UBIFS, ubifs, 0) \
 	func(MMC, mmc, 0) \
 	func(MMC, mmc, 2) \
 	func(PXE, pxe, na)