Call InstallFile to install files in soong built filesystem

platform_compat_config modules install files in `system/etc`, but the
files are missing from the soong-defined system image.
Calling InstallFile solves the problem.

Bug: 339133685
Test: m aosp_cf_system_x86_64
Change-Id: I46d5e75424a85108d0b478e4f0143f16ee26b53e
diff --git a/java/platform_compat_config.go b/java/platform_compat_config.go
index 7cc6231..67ed84e 100644
--- a/java/platform_compat_config.go
+++ b/java/platform_compat_config.go
@@ -109,23 +109,13 @@
 	p.installDirPath = android.PathForModuleInstall(ctx, "etc", "compatconfig")
 	p.installConfigFile = android.PathForModuleInstall(ctx, "etc", "compatconfig", p.configFile.Base())
 	rule.Build(configFileName, "Extract compat/compat_config.xml and install it")
-}
-
-func (p *platformCompatConfig) FilesToInstall() android.InstallPaths {
-	return android.InstallPaths{p.installConfigFile}
+	ctx.InstallFile(p.installDirPath, p.configFile.Base(), p.configFile)
 }
 
 func (p *platformCompatConfig) AndroidMkEntries() []android.AndroidMkEntries {
 	return []android.AndroidMkEntries{android.AndroidMkEntries{
 		Class:      "ETC",
 		OutputFile: android.OptionalPathForPath(p.configFile),
-		Include:    "$(BUILD_PREBUILT)",
-		ExtraEntries: []android.AndroidMkExtraEntriesFunc{
-			func(ctx android.AndroidMkExtraEntriesContext, entries *android.AndroidMkEntries) {
-				entries.SetString("LOCAL_MODULE_PATH", p.installDirPath.String())
-				entries.SetString("LOCAL_INSTALLED_MODULE_STEM", p.configFile.Base())
-			},
-		},
 	}}
 }