docs: Drop the kernel pin and HDMI refresh boost descriptions

ui/qml/Main.qml

@@ -72,8 +72,8 @@ ApplicationWindow {
         poweroff: { label: "Power-off fix", hint: "Stays off after shutting down",
                     body: "With recent kernels the Steam Machine starts again right after shutting down: the firmware leaves a wake bit set, and newer kernels (7.2, and updates of 6.x, 7.0 and 7.1) no longer clear it. Valve's own kernel clears it; this small module does the same right before power-off.",
                     changes: ["steamify-fremont-poweroff module for each installed kernel (DKMS)", "Only on a Steam Machine, only touches that one wake bit", "Off: recent kernels may start it again after shutting down"] },
-        kpin: { label: "Pin the kernel", hint: "No longer needed: untick for the current kernel",
-                body: "Keeps the Steam Machine on CachyOS kernel 7.1.6, which older versions of Steamify needed to shut down properly. The power-off fix handles that now. Untick it to go back to CachyOS's current kernel (HDMI refresh boost goes with it: newer kernels read the display's fast modes and do HDMI 2.1 themselves).",
+        kpin: { label: "Pin the kernel", hint: "Untick for CachyOS's current kernel",
+                body: "Keeps the Steam Machine on CachyOS kernel 7.1.6. Untick it to go back to CachyOS's current kernel; HDMI refresh boost goes with it.",
                 changes: ["linux-cachyos from Steamify's release (signature checked)", "Kept in /var/cache/steamify/kernel", "Added to IgnorePkg"] },
         hdmi: { label: "HDMI refresh boost", hint: "Higher refresh rates over HDMI",
                 body: "The pinned kernel keeps many HDMI displays at 60 Hz. Turning this on shows which refresh rates your display can run at the desktop resolution; you pick them, and each one is tried for 15 seconds so you can check the picture before it's installed.",