Remove Base_dir from non system non recovery filesystem

vendor.img/product.img... built by make do not assemble the artifacts in
a $partition subdirectory. This CL adds this to soong built img files,
and updates the symmlinks.

Test: soong_generated_system_filesystem_test m soong_generated_vendor_filesystem_test soong_generated_product_filesystem_test
Change-Id: Ia5feaf85bb49d552b93698c50998d8df7575e44a
diff --git a/filesystem/filesystem.go b/filesystem/filesystem.go
index 84384a5..b9cb076 100644
--- a/filesystem/filesystem.go
+++ b/filesystem/filesystem.go
@@ -457,7 +457,7 @@
 }
 
 func (f *filesystem) appendToEntry(ctx android.ModuleContext, installedFile android.Path) {
-	partitionBaseDir := android.PathForModuleOut(ctx, "root", f.partitionName()).String() + "/"
+	partitionBaseDir := android.PathForModuleOut(ctx, "root", proptools.String(f.properties.Base_dir)).String() + "/"
 
 	relPath, inTargetPartition := strings.CutPrefix(installedFile.String(), partitionBaseDir)
 	if inTargetPartition {