Boot: Replace flash partitioning terminology

This change replaces the slot 0/1 terminology with
primary/secondary slot and replaces FLASH_AREA_IMAGE_0/1
with FLASH_AREA_IMAGE_PRIMARY/SECONDARY. This naming
convention fits better to platforms with multiple images
and it is also an architecture agnostic alternative.

Change-Id: I5def429a076024831a702700736d9769a0b2301f
Signed-off-by: David Vincze <david.vincze@arm.com>
diff --git a/bl2/ext/mcuboot/bootutil/src/bootutil_priv.h b/bl2/ext/mcuboot/bootutil/src/bootutil_priv.h
index 1eb5a4a..c8a1c8a 100644
--- a/bl2/ext/mcuboot/bootutil/src/bootutil_priv.h
+++ b/bl2/ext/mcuboot/bootutil/src/bootutil_priv.h
@@ -119,17 +119,20 @@
 #endif
 
 /** Number of image slots in flash; currently limited to two. */
-#define BOOT_NUM_SLOTS             2
+#define BOOT_NUM_SLOTS                  2
 
 /** Maximum number of image sectors supported by the bootloader. */
-#define BOOT_STATUS_STATE_COUNT    3
+#define BOOT_STATUS_STATE_COUNT         3
 
-#define BOOT_STATUS_SOURCE_NONE    0
-#define BOOT_STATUS_SOURCE_SCRATCH 1
-#define BOOT_STATUS_SOURCE_SLOT0   2
+#define BOOT_PRIMARY_SLOT               0
+#define BOOT_SECONDARY_SLOT             1
 
-#define BOOT_FLAG_IMAGE_OK         0
-#define BOOT_FLAG_COPY_DONE        1
+#define BOOT_STATUS_SOURCE_NONE         0
+#define BOOT_STATUS_SOURCE_SCRATCH      1
+#define BOOT_STATUS_SOURCE_PRIMARY_SLOT 2
+
+#define BOOT_FLAG_IMAGE_OK              0
+#define BOOT_FLAG_COPY_DONE             1
 
 extern const uint32_t BOOT_MAGIC_SZ;
 
@@ -252,11 +255,11 @@
     int rc;
 
     switch (flash_area) {
-    case FLASH_AREA_IMAGE_0:
-        slot = 0;
+    case FLASH_AREA_IMAGE_PRIMARY:
+        slot = BOOT_PRIMARY_SLOT;
         break;
-    case FLASH_AREA_IMAGE_1:
-        slot = 1;
+    case FLASH_AREA_IMAGE_SECONDARY:
+        slot = BOOT_SECONDARY_SLOT;
         break;
     default:
         return BOOT_EFLASH;
@@ -297,15 +300,15 @@
     int rc;
 
     switch (flash_area) {
-    case FLASH_AREA_IMAGE_0:
+    case FLASH_AREA_IMAGE_PRIMARY:
         num_sectors = BOOT_MAX_IMG_SECTORS;
-        out_sectors = state->imgs[0].sectors;
-        out_num_sectors = &state->imgs[0].num_sectors;
+        out_sectors = state->imgs[BOOT_PRIMARY_SLOT].sectors;
+        out_num_sectors = &state->imgs[BOOT_PRIMARY_SLOT].num_sectors;
         break;
-    case FLASH_AREA_IMAGE_1:
+    case FLASH_AREA_IMAGE_SECONDARY:
         num_sectors = BOOT_MAX_IMG_SECTORS;
-        out_sectors = state->imgs[1].sectors;
-        out_num_sectors = &state->imgs[1].num_sectors;
+        out_sectors = state->imgs[BOOT_SECONDARY_SLOT].sectors;
+        out_num_sectors = &state->imgs[BOOT_SECONDARY_SLOT].num_sectors;
         break;
     default:
         return -1;