loader: Silence Wmissing-field-initializers warnings (#499)

Specifying 0 as the initial entry of a structure is a C-ism. C++ permits
using an empty set of braces to signify the same behavior, silencing
missing initializer warnings.

stratosphere/loader/source/ldr_content_management.cpp

@@ -29,8 +29,8 @@
 
 #include "ini.h"
 
-static FsFileSystem g_CodeFileSystem = {0};
-static FsFileSystem g_HblFileSystem = {0};
+static FsFileSystem g_CodeFileSystem = {};
+static FsFileSystem g_HblFileSystem = {};
 
 static std::vector<u64> g_created_titles;
 static bool g_has_initialized_fs_dev = false;