Update OpenAL-soft to 1.23.1-bc7cb17.

libs/openal-soft/examples/alhrtf.c

@@ -40,6 +40,8 @@
 
 #include "common/alhelpers.h"
 
+#include "win_main_utf8.h"
+
 
 #ifndef M_PI
 #define M_PI                         (3.14159265358979323846)
@@ -121,7 +123,7 @@ static ALuint LoadSound(const char *filename)
     free(membuf);
     sf_close(sndfile);
 
-    /* Check if an error occured, and clean up if so. */
+    /* Check if an error occurred, and clean up if so. */
     err = alGetError();
     if(err != AL_NO_ERROR)
     {