Normalize position of header guard

This is the common header guard idiom:

    /*
     * File comment
     */

    #ifndef GUARD_SYMBOL_H
    #define GUARD_SYMBOL_H

    ... actual contents ...

    #endif

A few of our headers have some #include before the guard.
target/tilegx/spr_def_64.h has #ifndef __DOXYGEN__ outside the guard.
A few more have the #define elsewhere.

Change them to match the common idiom.  For spr_def_64.h, that means
dropping #ifndef __DOXYGEN__.  While there, rename guard symbols to
make scripts/clean-header-guards.pl happy.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190604181618.19980-2-armbru@redhat.com>
[Rebased with conflicts resolved automatically]
diff --git a/tests/io-channel-helpers.h b/tests/io-channel-helpers.h
index fedc64f..bb2de6f 100644
--- a/tests/io-channel-helpers.h
+++ b/tests/io-channel-helpers.h
@@ -15,13 +15,12 @@
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
- *
  */
 
-#include "io/channel.h"
+#ifndef TEST_IO_CHANNEL_HELPERS_H
+#define TEST_IO_CHANNEL_HELPERS_H
 
-#ifndef TEST_IO_CHANNEL_HELPERS
-#define TEST_IO_CHANNEL_HELPERS
+#include "io/channel.h"
 
 typedef struct QIOChannelTest QIOChannelTest;
 
@@ -39,4 +38,4 @@
 
 void qio_channel_test_validate(QIOChannelTest *test);
 
-#endif /* TEST_IO_CHANNEL_HELPERS */
+#endif /* TEST_IO_CHANNEL_HELPERS_H */