Add a generic hasKaleidoWfm device cap

Because handling those without screwing with wfm priorities is going to
be a bitch.

frontend/device/generic/device.lua

@@ -62,6 +62,7 @@ local Device = {
     hasExternalSD = no, -- or other storage volume that cannot be accessed using the File Manager
     canHWDither = no,
     canHWInvert = no,
+    hasKaleidoWfm = no,
     canDoSwipeAnimation = no,
     canModifyFBInfo = no, -- some NTX boards do wonky things with the rotate flag after a FBIOPUT_VSCREENINFO ioctl
     canUseCBB = yes, -- The C BB maintains a 1:1 feature parity with the Lua BB, except that is has NO support for BB4, and limited support for BBRGB24

frontend/device/kobo/device.lua

@@ -836,6 +836,11 @@ function Kobo:init()
         self.canHWDither = yes
     end
 
+    -- Enable Kaleido waveform modes on supported devices
+    if self:hasColorScreen() and self:isMTK() then
+        self.hasKaleidoWfm = yes
+    end
+
     -- NOTE: Devices with an AW99703 frontlight PWM controller feature a hardware smooth ramp when setting the frontlight intensity.
     ---      A side-effect of this behavior is that if you queue a series of intensity changes ending at 0,
     ---      it won't ramp *at all*, jumping straight to zero instead.