Fix Mac build errors in drcachesim
Fix Mac build errors in drcachesim

Updates DR to 7e7b8ba to fix Mac build errors in drcachesim

code4bones/drmemory,LohithBlaze/drmemory,LohithBlaze/drmemory,LohithBlaze/drmemory,LohithBlaze/drmemory,code4bones/drmemory,code4bones/drmemory,code4bones/drmemory,code4bones/drmemory,LohithBlaze/drmemory