HANG api.static_prepop on aarch64

Split from #1578

This test hangs every time on the tx1:

derek@tx1:~/dr/build$ ctest -V -R static_prepop
UpdateCTestConfiguration  from :/home/derek/dr/build/DartConfiguration.tcl
Parse Config file:/home/derek/dr/build/DartConfiguration.tcl
UpdateCTestConfiguration  from :/home/derek/dr/build/DartConfiguration.tcl
Parse Config file:/home/derek/dr/build/DartConfiguration.tcl
Test project /home/derek/dr/build
Constructing a list of tests
Done constructing a list of tests
Updating test list for fixtures
Added 0 tests to meet fixture requirements
Checking test dependency graph...
Checking test dependency graph end
test 224
    Start 224: code_api|api.static_prepop

224: Test command: /home/derek/dr/build/bin64/runstats "-s" "90" "-killpg" "-silent" "-env" "LD_LIBRARY_PATH" "/home/derek/dr/build/lib64/debug:/home/derek/dr/build/ext/lib64/debug:" "-env" "DYNAMORIO_OPTIONS" "-stderr_mask 0xC -dumpcore_mask 0 -code_api" "/home/derek/dr/build/suite/tests/bin/api.static_prepop"
224: Test timeout computed to be: 1500
224: pre-DR init
224: in dr_client_main
224: bb asm_func
224: bb asm_label1
224: bb asm_label2
224: bb asm_label3
224: bb asm_return
224: pre-DR start
^C