Build boot.img with soong

Bug: 377562951
Test: m nothing
Change-Id: Icb0510eb457814fca0cfeece76e8e584a7c17350
diff --git a/android/variable.go b/android/variable.go
index 2d43c6d..88cf5a5 100644
--- a/android/variable.go
+++ b/android/variable.go
@@ -610,6 +610,7 @@
 	CopyImagesForTargetFilesZip    bool   `json:",omitempty"`
 
 	// Boot image stuff
+	BuildingRamdiskImage            bool   `json:",omitempty"`
 	ProductBuildBootImage           bool   `json:",omitempty"`
 	ProductBuildInitBootImage       bool   `json:",omitempty"`
 	BoardUsesRecoveryAsBoot         bool   `json:",omitempty"`
@@ -618,6 +619,7 @@
 	BoardBootimagePartitionSize     string `json:",omitempty"`
 	BoardInitBootimagePartitionSize string `json:",omitempty"`
 	BoardBootHeaderVersion          string `json:",omitempty"`
+	TargetKernelPath                string `json:",omitempty"`
 
 	// Avb (android verified boot) stuff
 	BoardAvbEnable          bool                                `json:",omitempty"`