Input: Add event-codes for macro keys found on various keyboards

Input: Add event-codes for macro keys found on various keyboards

Various keyboards have macro keys, which are intended to have user
programmable actions / key-sequences bound to them. In some cases these
macro keys are actually programmable in hardware, but more often they
basically are just extra keys and the playback of the key-sequence is done
by software running on the host.

One example of keyboards with macro-keys are various "internet" / "office"
keyboards have a set of so-called "Smart Keys", typically a set of 4 keys
labeled "[A]" - "[D]".

Another example are gaming keyboards, such as the Logitech G15 Gaming
keyboard, which has 18 "G"aming keys labeled "G1" to G18", 3 keys to select
macro presets labeled "M1" - "M3" and a key to start recording a macro
called "MR" note that even though there us a record key everything is
handled in sw on the host.

Besides macro keys the G15 (and other gaming keyboards) also has a buildin
LCD panel where the contents are controlled by the host. There are 5 keys
directly below the LCD intended for controlling a menu shown on the LCD.

The Microsoft SideWinder X6 keyboard is another gaming keyboard example,
this keyboard has 30 "S"idewinder keys and a key to cycle through
macro-presets.

After discussion between various involved userspace people we've come to
the conclusion that since these are all really just extra keys we should
simply treat them as such and give them their own event-codes, see:
https://github.com/libratbag/libratbag/issues/172

This commit adds the following new KEY_ defines for this:

KEY_MACRO1 - KEY_MACRO30. KEY_MACRO_RECORD_START/-STOP,
KEY_MACRO_PRESET_CYCLE, KEY_MACRO_PRESET1 - KEY_MACRO_PRESET3,
KEY_KBD_LCD_MENU1 - KEY_KBD_LCD_MENU5.

The defines leave room for adding some more LCD-menu, preset or macro keys,
the maximum values above are based on the maximum values to support all
currently known internet, office and gaming keyboards.

BugLink: https://github.com/libratbag/libratbag/issues/172
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>