Add -Lformat option to format .hal files

Formats .hal files.

Bug: 137553653
Test: hidl-gen -Lformat <IFACE>
Test: aosp/1051701
Test: hidl-gen -Lformat (google-interfaces) & hidl-gen -Lcheck
(google-interfaces)
Change-Id: I5aa554d99fd4977acb7939d8c793081680a3f598
diff --git a/Annotation.cpp b/Annotation.cpp
index 438cff6..4c9637f 100644
--- a/Annotation.cpp
+++ b/Annotation.cpp
@@ -158,7 +158,7 @@
 
         const AnnotationParam* param = mParams->at(i);
 
-        out << param->getName() << "=";
+        out << param->getName() << " = ";
 
         const std::vector<std::string>& values = param->getValues();
         if (values.size() > 1) {