message: test: Make valgrind.supp work on aarch64
  The equivalent suppression on aarch64 looks like:
  {
  <insert_a_suppression_name_here>
  Memcheck:Param
  pwrite64(buf)
  fun:__libc_pwrite64
  fun:pwrite
  fun:__os_io
  obj:/usr/lib/aarch64-linux-gnu/libdb_cxx-5.3.so
  fun:__log_flush_int
  fun:__log_flush
  fun:__memp_sync_int
  fun:__db_sync
  fun:__db_refresh
  fun:__db_close
  fun:__fop_subdb_setup
  fun:__db_open
  fun:__db_open_pp
  }
diff: -# Valgrind suppressions file for Bitcoin.
  -#
  -# Includes known Valgrind warnings in our dependencies that cannot be fixed
  -# in-tree.
  +# This valgrind suppressions file includes known Valgrind warnings in our
  +# dependencies that cannot be fixed in-tree.
  #
  # Example use:
  # $ valgrind --suppressions=contrib/valgrind.supp src/test/test_bitcoin
  # --error-limit=no src/test/test_bitcoin
  #
  # Note that suppressions may depend on OS and/or library versions.
  +# Tested on:
  +# * aarch64 (Ubuntu 20.04 system libs, without gui)
  +# * x86_64 (Ubuntu 18.04 system libs, without gui)
  {
  Suppress libstdc++ warning - https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65434
  Memcheck:Leak
  Suppress libdb warning
  Memcheck:Param
  pwrite64(buf)
  - fun:pwrite
  - fun:__os_io
  + ...
  obj:*/libdb_cxx-*.so
  }
  {
  