generic: add linux 4.1 support

Boot tested: http://pastebin.com/L6aAb9xj

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
[jogo:
  update to 4.1 final
  add patches added since submission
  delete patches applied in later rcs
  restore commit messages in 220-gc-sections and 304-mips_disable_fpu
  fix 050-backport_netfilter_rtcache to match new API
  update inlined dma ops with upstream changes
  add missing config symbols
  enabled CONFIG_MULTIUSER
  update kmod defintions for 4.1
]
Signed-off-by: Jonas Gorski <jogo@openwrt.org>

SVN-Revision: 46112

target/linux/generic/patches-4.1/480-mtd-set-rootfs-to-be-root-dev.patch

@@ -0,0 +1,26 @@
+--- a/drivers/mtd/mtdcore.c
++++ b/drivers/mtd/mtdcore.c
+@@ -39,6 +39,7 @@
+ #include <linux/slab.h>
+ #include <linux/reboot.h>
+ #include <linux/kconfig.h>
++#include <linux/root_dev.h>
+ 
+ #include <linux/mtd/mtd.h>
+ #include <linux/mtd/partitions.h>
+@@ -448,6 +449,15 @@ int add_mtd_device(struct mtd_info *mtd)
+ 	   of this try_ nonsense, and no bitching about it
+ 	   either. :) */
+ 	__module_get(THIS_MODULE);
++
++	if (!strcmp(mtd->name, "rootfs") &&
++	    config_enabled(CONFIG_MTD_ROOTFS_ROOT_DEV) &&
++	    ROOT_DEV == 0) {
++		pr_notice("mtd: device %d (%s) set to be root filesystem\n",
++			  mtd->index, mtd->name);
++		ROOT_DEV = MKDEV(MTD_BLOCK_MAJOR, mtd->index);
++	}
++
+ 	return 0;
+ 
+ fail_added: