disk: convert CONFIG_ISO_PARTITION to Kconfig

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Signed-off-by: Patrick Delaunay <patrick.delaunay73@gmail.com>
diff --git a/configs/O2I_defconfig b/configs/O2I_defconfig
index a36f05d..2c8d3e1 100644
--- a/configs/O2I_defconfig
+++ b/configs/O2I_defconfig
@@ -12,5 +12,6 @@
 CONFIG_CMD_PING=y
 CONFIG_CMD_FAT=y
 CONFIG_MAC_PARTITION=y
+CONFIG_ISO_PARTITION=y
 # CONFIG_PCI is not set
 CONFIG_OF_LIBFDT=y