Example build: ./BUILD/compile-pentium64-valgrind-max

Fixes:
- sp-no-valgrind failed if binary was built for valgrind as in this case
  mem_root is allocated in very small hunks which the test cannot handle.
  Fixed by testing of valgrind build
- truncate_notembedded failed in reap because of more memory used.
  Fixed by allowing reap to fail too