arc770: move arc patches to target/linux/generic

Given those patches are relevant to any ARC platform and even
ISA version it makes perfect sense for patches to exist
in one place instead of being duplicated for each new ARC-based ASIC.

Note this is a prerequisite for upstreaming of ARC HS38 support in
OpenWRT.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Felix Fietkau <nbd@openwrt.org>
Cc: Jo-Philipp Wich <jow@openwrt.org>
Cc: Jonas Gorski <jogo@openwrt.org>

SVN-Revision: 48241

target/linux/generic/patches-4.4/331-arc-remove-dependency-on-DEVTMPFS.patch

@@ -0,0 +1,36 @@
+From adfbf9e6cad93281cffceab078e7f6f2a8e094f9 Mon Sep 17 00:00:00 2001
+From: Alexey Brodkin <abrodkin@synopsys.com>
+Date: Thu, 13 Aug 2015 01:56:02 +0300
+Subject: [PATCH 1/2] openwrt: arc - remove dependency on DEVTMPFS
+
+OpenWRT builds initramfs so that it doesn't require DEVTMPFS so dropping
+this dependency. That helps to escape 2 separate kernel rebuilds with
+and without initramfs.
+
+2 builds happen because OpenWRT first builds kernel and later modules.
+When building entire kernel with simple "make" INITRAMFS sets to a real
+value and so was triggering DEVTMPFS selection. Then when building only
+modules with "make modules" command INITRAMFS is zeroed and so kernel
+config was changing that lead to full kernel rebuild.
+
+Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
+---
+ arch/arc/Kconfig | 2 --
+ 1 file changed, 2 deletions(-)
+
+diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
+index 6312f60..a95bab3 100644
+--- a/arch/arc/Kconfig
++++ b/arch/arc/Kconfig
+@@ -12,8 +12,6 @@ config ARC
+ 	select BUILDTIME_EXTABLE_SORT
+ 	select COMMON_CLK
+ 	select CLONE_BACKWARDS
+-	# ARC Busybox based initramfs absolutely relies on DEVTMPFS for /dev
+-	select DEVTMPFS if !INITRAMFS_SOURCE=""
+ 	select GENERIC_ATOMIC64
+ 	select GENERIC_CLOCKEVENTS
+ 	select GENERIC_FIND_FIRST_BIT
+-- 
+2.4.3
+