m68k: muldi3: Use semicolon instead of comma

This code works, but it is cleaner to use a semicolon at the end of a
statement instead of a comma.

Extracted from a big anonymous patch by Julia Lawall
<julia.lawall@inria.fr>.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20210914073155.3883532-1-geert@linux-m68k.org

arch/m68k/lib/muldi3.c

@@ -84,7 +84,7 @@ __muldi3 (DItype u, DItype v)
   DIunion w;
   DIunion uu, vv;
 
-  uu.ll = u,
+  uu.ll = u;
   vv.ll = v;
 
   w.ll = __umulsidi3 (uu.s.low, vv.s.low);