xfree86: os-support: drop obsolete Solaris specific LED defines

Historical legacy: the LED ID defines have/had different naming across various platforms - for better portability of the keyboard driver, those have been aliased to BSD's naming scheme. Meanwhile, lots of ancient platforms have been died or moved to other drivers (eg. Linux went to either evdev or libinput and not supported by the xf86-input-keyboard driver anymore).

The only remaining possible consumer is Solaris. But it has it's own dedicated code (sun_kbd.c in xf86-input-keyboard), which already using the Solaris' naming.

Therefore, there's no actual consumer of them left, so we can drop them.

Signed-off-by: Enrico Weigelt, metux IT consult info@metux.net