ntdll: Fix growing the shm_addrs array.

Fixes an issue exposed by the last patch and visible in GTA V. Presumably
this didn't show up earlier because applications usually don't create large
numbers of semaphores or mutexes, and previously events didn't use shared
memory.

dlls/ntdll/esync.c

@@ -142,8 +142,9 @@ static void *get_shm( unsigned int idx )
 
  if (entry >= shm_addrs_size)
  {
- shm_addrs_size *= 2;
- if (!(shm_addrs = RtlReAllocateHeap( GetProcessHeap(), HEAP_ZERO_MEMORY, shm_addrs, shm_addrs_size )))
+ shm_addrs_size = entry + 1;
+ if (!(shm_addrs = RtlReAllocateHeap( GetProcessHeap(), HEAP_ZERO_MEMORY,
+ shm_addrs, shm_addrs_size * sizeof(shm_addrs[0]) )))
  ERR("Failed to grow shm_addrs array to size %d.\n", shm_addrs_size);
  }