Expose android.filesToInstall

It will be used by the cvd_host_package module type to gather installed
files and package them in a distributable format.

Bug: 168086242
Test: m

Change-Id: I3af6dcda0bce1f298b1500fbac311c9593ddf375
diff --git a/android/test_suites.go b/android/test_suites.go
index 34e487e..19444a8 100644
--- a/android/test_suites.go
+++ b/android/test_suites.go
@@ -41,7 +41,7 @@
 					files[testSuite] = make(map[string]InstallPaths)
 				}
 				name := ctx.ModuleName(m)
-				files[testSuite][name] = append(files[testSuite][name], tsm.filesToInstall()...)
+				files[testSuite][name] = append(files[testSuite][name], tsm.FilesToInstall()...)
 			}
 		}
 	})