Add <xmlfile> to manifest / comp mat.

manifest.xml is allowed to contain <xmlfile> that is similar to:
<xmlfile>
    <name>media_profile</name>
    <version>1.0</version>
    <path>/path/to/media_profile_v1_0.xml</path>
</xmlfile>

For compatibility-matrix.xml
<xmlfile format="dtd" optional="false">
    <name>media_profile</name>
    <version>1.0-1</version>
    <path>/path/to/media_profile_v1_1.dtd</path>
</xmlfile>

The <path> tag is optional. See test/main.cpp for examples.

Test: libvintf_test
Test: vintf_object_test

Bug: 38359330

Change-Id: I0a921f32d023e1ba9c54ea6e898bb385fc7abd4f
diff --git a/parse_string.cpp b/parse_string.cpp
index d412ac4..4d7ae9a 100644
--- a/parse_string.cpp
+++ b/parse_string.cpp
@@ -97,6 +97,7 @@
 DEFINE_PARSE_STREAMIN_FOR_ENUM(KernelConfigType);
 DEFINE_PARSE_STREAMIN_FOR_ENUM(Tristate);
 DEFINE_PARSE_STREAMIN_FOR_ENUM(SchemaType);
+DEFINE_PARSE_STREAMIN_FOR_ENUM(XmlSchemaFormat);
 
 std::ostream &operator<<(std::ostream &os, const KernelConfigTypedValue &kctv) {
     switch (kctv.mType) {