Remove PlatformVndkVersion property

Platform VNDK version is no longer available based on VNDK deprecation.
Remove all code using Platform VNDK version.

Bug: 330100430
Test: AOSP CF build succeeded
Change-Id: I7d0f7e23eff5d153346890f242a94b78bad6736b
diff --git a/apex/apex.go b/apex/apex.go
index bc91407..f24590f 100644
--- a/apex/apex.go
+++ b/apex/apex.go
@@ -737,7 +737,7 @@
 // image variation name.
 func (a *apexBundle) getImageVariationPair(deviceConfig android.DeviceConfig) (string, string) {
 	if a.vndkApex {
-		return cc.VendorVariationPrefix, a.vndkVersion(deviceConfig)
+		return cc.VendorVariationPrefix, a.vndkVersion()
 	}
 
 	prefix := android.CoreVariation
@@ -746,9 +746,6 @@
 		if a.SocSpecific() || a.DeviceSpecific() {
 			prefix = cc.VendorVariationPrefix
 			vndkVersion = deviceConfig.VndkVersion()
-		} else if a.ProductSpecific() {
-			prefix = cc.ProductVariationPrefix
-			vndkVersion = deviceConfig.PlatformVndkVersion()
 		}
 	} else {
 		if a.SocSpecific() || a.DeviceSpecific() {
@@ -757,9 +754,6 @@
 			prefix = cc.ProductVariation
 		}
 	}
-	if vndkVersion == "current" {
-		vndkVersion = deviceConfig.PlatformVndkVersion()
-	}
 
 	return prefix, vndkVersion
 }