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/charon_defconfig b/configs/charon_defconfig
index 5b986e7..95801d7 100644
--- a/configs/charon_defconfig
+++ b/configs/charon_defconfig
@@ -20,6 +20,7 @@
 CONFIG_CMD_EXT2=y
 CONFIG_CMD_FAT=y
 CONFIG_MAC_PARTITION=y
+CONFIG_ISO_PARTITION=y
 CONFIG_USB=y
 CONFIG_USB_STORAGE=y
 CONFIG_CONSOLE_EXTRA_INFO=y