Build fix for llvm 22

Index: src/billard3d.c
--- src/billard3d.c.orig
+++ src/billard3d.c
@@ -5100,7 +5100,7 @@ int main( int argc, char *argv[] )
 
 #if __BYTE_ORDER == __BIG_ENDIAN
        {
-          char *snd=ball_ball_snd.data;
+          char *snd=(char *)ball_ball_snd.data;
           for(i=0;i<ball_ball_snd.len;i+=2)
           {
              char t=snd[i];
