ARM: tegra: lg-x3: Add node for capacitive buttons

Both smartphones have capacitive buttons but only P895 supports RMI4
function 1A (0D touch), while P880 exposes buttons area as a region of the
touchscreen.

Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

Author: clamor-s

arch/arm/boot/dts/nvidia/tegra30-lg-p895.dts

@@ -109,6 +109,12 @@
 				syna,clip-x-high = <1535>;
 				syna,clip-y-high = <2047>;
 			};
+
+			rmi4-f1a@1a {
+				reg = <0x1a>;
+
+				linux,keycodes = <KEY_BACK KEY_HOME KEY_MENU KEY_SEARCH>;
+			};
 		};
 	};