[POWERPC] PS3: Remove duplicate variable assignement

A minor change to remove a duplicate variable assignement in ps3_mm_shutdown();

Signed-off-by: Geoff Levand <[e-mail]>
Signed-off-by: Paul Mackerras <[e-mail]>

arch/powerpc/platforms/ps3/mm.c

···
 void ps3_mm_shutdown(void)
 {
 	ps3_mm_region_destroy(&map.r1);
-	map.total = map.rm.size;
 }