linux 4.15.4: add missing patches

target/linux/patches/4.15.4/h8300.patch

@@ -0,0 +1,12 @@
+diff -Nur linux-4.13.2.orig/arch/h8300/Kconfig.cpu linux-4.13.2/arch/h8300/Kconfig.cpu
+--- linux-4.13.2.orig/arch/h8300/Kconfig.cpu	2017-09-13 23:21:49.000000000 +0200
++++ linux-4.13.2/arch/h8300/Kconfig.cpu	2017-09-16 18:32:15.263759679 +0200
+@@ -96,4 +96,8 @@
+         hex "Load offset"
+ 	default 0
+ 
++config RAMBASE
++	hex "RAM base address"
++	default 0x400000
++
+ endmenu

target/linux/patches/4.15.4/or1k-more-ram.patch

@@ -0,0 +1,12 @@
+diff -Nur linux-4.8.11.orig/arch/openrisc/boot/dts/or1ksim.dts linux-4.8.11/arch/openrisc/boot/dts/or1ksim.dts
+--- linux-4.8.11.orig/arch/openrisc/boot/dts/or1ksim.dts	2016-11-26 09:57:13.000000000 +0100
++++ linux-4.8.11/arch/openrisc/boot/dts/or1ksim.dts	2016-12-04 14:39:46.092952799 +0100
+@@ -11,7 +11,7 @@
+ 
+ 	memory@0 {
+ 		device_type = "memory";
+-		reg = <0x00000000 0x02000000>;
++		reg = <0x00000000 0x04000000>;
+ 	};
+ 
+ 	cpus {