build_image.py recognize BOARD_VENDORIMAGE_PARTITION_RESERVED_SIZE

Test: `make vendorimage`

Test: `make vendorimage` with the following:
    - install a large file to vendor image
    fails as expected (because _PARTITION_SIZE is exceeded)

Test: `make vendorimage` with the following:
    - set PRODUCT_USE_LOGICAL_PARTITIONS to true
    - set BOARD_VENDORIMAGE_PARTITION_RESERVED_SIZE
    fails as expected (BOARD_VENDORIMAGE_PARTITION_SIZE needs
    to be undefined)

Test: `make vendorimage` with the following:
    - install a large file to vendor image
    - set PRODUCT_USE_LOGICAL_PARTIIONS to true
    - add a small BOARD_VENDORIMAGE_PARTITION_RESERVED_SIZE
    - remove BOARD_VENDORIMAGE_PARTITION_SIZE
    build succeeds.

Bug: 79106666

Change-Id: Ica8fdce64e8f37d91e66e3d49c0c74fadd15a832
diff --git a/core/config.mk b/core/config.mk
index f92375c..17c9eab 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -936,6 +936,13 @@
 endif
 endif
 
+ifneq ($(BOARD_VENDORIMAGE_PARTITION_SIZE),)
+ifneq ($(BOARD_VENDORIMAGE_PARTITION_RESERVED_SIZE),)
+$(error Should not define BOARD_VENDORIMAGE_PARTITION_SIZE and \
+    BOARD_VENDORIMAGE_PARTITION_RESERVED_SIZE together)
+endif
+endif
+
 endif # USE_LOGICAL_PARTITIONS
 
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