evdev: fix build with old kernel headers

evdev: fix build with old kernel headers

* configure.ac: Check whether struct input_absinfo.resolution is defined
in <linux/input.h>.
* evdev.c (SYN_MAX): Add fallback definition.
(abs_ioctl): Wrap use of struct input_absinfo.resolution in #ifdef check.
(keycode_V2_ioctl, mtslots_ioctl, repeat_ioctl): Wrap in #ifdef checks.
(evdev_read_ioctl): Wrap in #ifdef checks the code that uses EV_SW,
EVIOCGREP, EVIOCGKEYCODE_V2, EVIOCGMTSLOTS, EVIOCGPROP, and EVIOCGSW.
(evdev_write_ioctl): Wrap in #ifdef checks the code that uses EVIOCSREP,
EVIOCSKEYCODE_V2, EVIOCSCLOCKID, and EVIOCREVOKE.