linker/bpm-sw.ld: align section to 8 bytes

This is good to ensure correct boundaries
on 64-bit systems.

linker/bpm-sw.ld

 SECTIONS
 {
-    .smio_mod_dispatch : ALIGN(4)
+    .smio_mod_dispatch : ALIGN(8)
     {
         _smio_mod_dispatch = .;
         KEEP(*(.smio_mod_dispatch))