Also support intrinsification for SerializersModule.serializer<T>()

method that fallbacks to module.getContextual().

plugins/kotlinx-serialization/testData/codegen/IntrinsicsAdvanced.kt

@@ -0,0 +1,32 @@
+// CURIOUS_ABOUT: test, getSer
+// WITH_STDLIB
+
+import kotlinx.serialization.*
+import kotlinx.serialization.json.*
+import kotlinx.serialization.modules.*
+
+@Serializable
+class Simple(val firstName: String, val lastName: String)
+
+class NoSer
+
+class NoSerGeneric<T>
+
+val module = SerializersModule {}
+
+inline fun <reified T: Any> getSer(module: SerializersModule): KSerializer<T> {
+    return module.serializer()
+}
+
+fun test() {
+    module.serializer<Simple>()
+    module.serializer<NoSer>()
+    module.serializer<List<Simple>>()
+    module.serializer<List<NoSer>>()
+
+    getSer<Simple>(module)
+    getSer<NoSer>(module)
+
+    getSer<NoSerGeneric<Simple>>(module)
+    getSer<NoSerGeneric<NoSer>>(module)
+}