ARM: mach-shmobile: mackerel: update defconfig

* Enable ARM_APPENDED_DTB

  Typically the bootloader of a mackerel board does not support DT
  so this option is useful

* Add "rw" to command line

  This appears to be necessary for a successful NFS-root boot

* Remove memchunk from kernel command line,
  it is not used outside of arch/sh

* Move command line to dts

  This brings us one small step closer to sharing defconfig
  between mackerel and other boards
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

arch/arm/boot/dts/sh7372-mackerel.dts

@@ -15,6 +15,10 @@ / {
 	model = "Mackerel (AP4 EVM 2nd)";
 	compatible = "renesas,mackerel";
 
+	chosen {
+		bootargs = "console=tty0, console=ttySC0,115200 earlyprintk=sh-sci.0,115200 root=/dev/nfs nfsroot=,tcp,v3 ip=dhcp mem=240m rw";
+	};
+
 	memory {
 		device_type = "memory";
 		reg = <0x40000000 0x10000000>;

arch/arm/configs/mackerel_defconfig

@@ -23,7 +23,7 @@ CONFIG_AEABI=y
 CONFIG_FORCE_MAX_ZONEORDER=15
 CONFIG_ZBOOT_ROM_TEXT=0x0
 CONFIG_ZBOOT_ROM_BSS=0x0
-CONFIG_CMDLINE="console=tty0, console=ttySC0,115200 earlyprintk=sh-sci.0,115200 root=/dev/nfs nfsroot=,tcp,v3 ip=dhcp memchunk.vpu=64m memchunk.veu0=8m memchunk.spu0=2m mem=240m"
+CONFIG_ARM_APPENDED_DTB=y
 CONFIG_KEXEC=y
 # CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS is not set
 CONFIG_PM=y