ARM: dts: lpc18xx: remove skeleton.dtsi include and fix unit address warnings

Removale of skeleton.dtsi allows us also to fix the following
warning from the dts compiler:
  Warning (unit_address_vs_reg): Node /memory has a reg or ranges property, but no unit name

by adding proper unit addresses to the memory nodes.

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>

arch/arm/boot/dts/lpc4350-hitex-eval.dts

@@ -33,7 +33,7 @@
 		stdout-path = &uart0;
 	};
 
-	memory {
+	memory@28000000 {
 		device_type = "memory";
 		reg = <0x28000000 0x800000>; /* 8 MB */
 	};