[nrf temphack] dfu: fix partition manager / mcuboot interaction

The removal of the scratch partition has broken the build for asset
tracker. There's probably a better way to fix it than this, but let's
get the build working again and figure it out.

Signed-off-by: Martí Bolívar <[email protected]>

Author: mbolivar-nordic

subsys/dfu/boot/mcuboot.c

@@ -76,7 +76,9 @@ struct mcuboot_v1_raw_header {
 
 #define FLASH_AREA_IMAGE_PRIMARY    PM_MCUBOOT_PRIMARY_ID
 #define FLASH_AREA_IMAGE_SECONDARY  PM_MCUBOOT_SECONDARY_ID
+#ifdef PM_MCUBOOT_SCRATCH_ID
 #define FLASH_AREA_IMAGE_SCRATCH    PM_MCUBOOT_SCRATCH_ID
+#endif
 
 #else