docs: Replace <structname> tags with back ticks

https://bugzilla.gnome.org/show_bug.cgi?id=731050

glib/gbookmarkfile.h

@@ -72,7 +72,7 @@ GQuark g_bookmark_file_error_quark (void);
 /**
  * GBookmarkFile:
  *
- * The <structname>GBookmarkFile</structname> struct contains only
+ * The `GBookmarkFile` structure contains only
  * private data and should not be directly accessed.
  */
 typedef struct _GBookmarkFile GBookmarkFile;

glib/gdatetime.h

@@ -91,7 +91,7 @@ typedef gint64 GTimeSpan;
 /**
  * GDateTime:
  *
- * <structname>GDateTime</structname> is an opaque structure whose members
+ * `GDateTime` is an opaque structure whose members
  * cannot be accessed directly.
  *
  * Since: 2.26

glib/gerror.h

@@ -36,8 +36,8 @@ G_BEGIN_DECLS
  * @code: error code, e.g. %G_FILE_ERROR_NOENT
  * @message: human-readable informative error message
  *
- * The <structname>GError</structname> structure contains
- * information about an error that has occurred.
+ * The `GError` structure contains information about
+ * an error that has occurred.
  */
 typedef struct _GError GError;
 

glib/gmain.h

@@ -42,7 +42,7 @@ typedef enum /*< flags >*/
 /**
  * GMainContext:
  *
- * The <structname>GMainContext</structname> struct is an opaque data
+ * The `GMainContext` struct is an opaque data
  * type representing a set of sources to be handled in a main loop.
  */
 typedef struct _GMainContext            GMainContext;
@@ -50,7 +50,7 @@ typedef struct _GMainContext            GMainContext;
 /**
  * GMainLoop:
  *
- * The <structname>GMainLoop</structname> struct is an opaque data type
+ * The `GMainLoop` struct is an opaque data type
  * representing the main event loop of a GLib or GTK+ application.
  */
 typedef struct _GMainLoop               GMainLoop;
@@ -58,7 +58,7 @@ typedef struct _GMainLoop               GMainLoop;
 /**
  * GSource:
  *
- * The <structname>GSource</structname> struct is an opaque data type
+ * The `GSource` struct is an opaque data type
  * representing an event source.
  */
 typedef struct _GSource                 GSource;
@@ -71,7 +71,7 @@ typedef struct _GSourcePrivate          GSourcePrivate;
  * @get: Called to extract the callback function and data from the
  *     callback object.
 
- * The <structname>GSourceCallbackFuncs</structname> struct contains
+ * The `GSourceCallbackFuncs` struct contains
  * functions for managing callback objects.
  */
 typedef struct _GSourceCallbackFuncs    GSourceCallbackFuncs;
@@ -104,7 +104,7 @@ typedef struct _GSourceCallbackFuncs    GSourceCallbackFuncs;
  *     are needed for this type of event source.
  * @finalize: Called when the source is finalized.
  *
- * The <structname>GSourceFuncs</structname> struct contains a table of
+ * The `GSourceFuncs` struct contains a table of
  * functions used to handle event sources in a generic manner.
  *
  * For idle sources, the prepare and check functions always return %TRUE

glib/goption.h

@@ -31,7 +31,7 @@ G_BEGIN_DECLS
 /**
  * GOptionContext:
  * 
- * A <structname>GOptionContext</structname> struct defines which options
+ * A `GOptionContext` struct defines which options
  * are accepted by the commandline option parser. The struct has only private 
  * fields and should not be directly accessed.
  */
@@ -40,12 +40,12 @@ typedef struct _GOptionContext GOptionContext;
 /**
  * GOptionGroup:
  *
- * A <structname>GOptionGroup</structname> struct defines the options in a single
+ * A `GOptionGroup` struct defines the options in a single
  * group. The struct has only private fields and should not be directly accessed.
  *
  * All options in a group share the same translation function. Libraries which
  * need to parse commandline options are expected to provide a function for
- * getting a <structname>GOptionGroup</structname> holding their options, which
+ * getting a `GOptionGroup` holding their options, which
  * the application can then add to its #GOptionContext.
  */
 typedef struct _GOptionGroup   GOptionGroup;