Defines starting with `o' in uae-0.8.29

• off_t src/tools/configure:2616
• O_NDELAY src/include/sysconfig.h.win32:39
• O_NONBLOCK src/serial.c:42
• open src/include/sysdeps.h:286
• opendir src/include/sysdeps.h:315
• OPTION_COLUMN src/tui.c:29
• OPTIONSFILENAME src/targets/t-acorn.h:9
• OPTIONS_IN_HOME src/targets/t-amiga.h:12
• OS_WITHOUT_MEMORY_MANAGEMENT src/od-amiga/memory.h:12