Remove unused variable to avoid compiler warning

[sherry-yuan]

../lib/acl_threadsupport/test/acl_threadsupport_test.cpp: In member function 'virtual void condvar_wait_signal_with_timeout_Test::testBody()':
../lib/acl_threadsupport/test/acl_threadsupport_test.cpp:445:7: warning: unused variable 'timedout' [-Wunused-variable]
   int timedout = 0;
       ^~~~~~~~

../test/acl_mem_test.cpp: In member function 'virtual void acl_mem_buffer_location_property_Test::testBody()':
../test/acl_mem_test.cpp:2812:10: warning: unused variable 'small_size' [-Wunused-variable]
   size_t small_size = bank_size / 1024;

Prerequisite of #85

[pcolberg]

Thanks @sherry-yuan! These warnings have been present since #48.