In the extremely unlikely event that inotify is not available (and,
therefore, HAVE_INOTIFY is not #defined), SDL will no-longer build.
This is because <unistd.h> is only included when HAVE_INOTIFY is
defined, and PR #4098 adds a call to access(…, F_OK), which requires
<unistd.h>.
(Note that the F_OK symbol is the only one which actually prevented
SDL from compiling, but both access() and close() fell back to implicit
definitions, which is a bit concerning.)
Fixes: 8d43f45a7b ("Don't use udev for joystick enumeration if running in a container")
db58166e9b