aidegen: Fix bug of generating module dependency information

Bug: 117588037
Test: cd $android_root;make aidegen;aidegen -m tradefed
Change-Id: I05712ef3243771605034e4e9a746b8e1081c3516
diff --git a/java/java.go b/java/java.go
index c5414f4..e5218bb 100644
--- a/java/java.go
+++ b/java/java.go
@@ -1757,7 +1757,7 @@
 	// solution to get the Import name.
 	name := j.Name()
 	if strings.HasPrefix(name, removedPrefix) {
-		name = strings.Trim(name, removedPrefix)
+		name = strings.TrimPrefix(name, removedPrefix)
 	}
 	return name
 }