kernel: backport patch for MTD_BCM47XXSFLASH dependency

This is required to update bcma without build breakage. One of bcma
patches changes BCMA_SFLASH dependency.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>

target/linux/generic/patches-4.4/042-0002-mtd-add-arch-dependency-for-MTD_BCM47XXSFLASH-symbol.patch

@@ -0,0 +1,41 @@
+From efacc699139e13f9d3ed8b47df92acb88ff8479f Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <zajec5@gmail.com>
+Date: Tue, 19 Jul 2016 09:08:32 +0200
+Subject: [PATCH] mtd: add arch dependency for MTD_BCM47XXSFLASH symbol
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+We dropped strict MIPS dependency for bcm47xxsflash driver in:
+commit 5651d6aaf489 ("mtd: bcm47xxsflash: use ioremap_cache() instead of
+KSEG0ADDR()") but using ioremap_cache still limits building it to few
+selected architectures only.
+
+A recent commit 57d8f7dd2132 ("bcma: allow enabling serial flash support
+on non-MIPS SoCs") automatically dropped MIPS dependency for
+MTD_BCM47XXSFLASH which broke building e.g. on powerpc and cris.
+
+The bcma change is alright as it doesn't break building bcma code in any
+way. MTD_BCM47XXSFLASH on the other hand should be limited to archs
+which need it and can build it (by providing ioremap_cache).
+
+Fixes: 57d8f7dd2132 ("bcma: allow enabling serial flash support on non-MIPS SoCs")
+Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
+Cc: Brian Norris <computersforpeace@gmail.com>
+Acked-by: Brian Norris <computersforpeace@gmail.com>
+Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
+---
+ drivers/mtd/devices/Kconfig | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/drivers/mtd/devices/Kconfig
++++ b/drivers/mtd/devices/Kconfig
+@@ -114,7 +114,7 @@ config MTD_SST25L
+ 
+ config MTD_BCM47XXSFLASH
+ 	tristate "R/O support for serial flash on BCMA bus"
+-	depends on BCMA_SFLASH
++	depends on BCMA_SFLASH && (MIPS || ARM)
+ 	help
+ 	  BCMA bus can have various flash memories attached, they are
+ 	  registered by bcma as platform devices. This enables driver for