toolchain: Bump ARC tools to arc-2017.09 release

This commit finally bumps ARC tools to the most recent arc-2017.09 release version.

ARC GNU tools of version arc-2017.09 bring some quite significant changes like:
 * Binutils v2.29 with additional ARC patches
 * GCC 7.1.1 with additional ARC patches
 * glibc 2.26 with additional ARC patches

More information on this release could be found here:
https://github.com/foss-for-synopsys-dwc-arc-processors/toolchain/releases/tag/arc-2017.09-release

Signed-off-by: Evgeniy Didin <didin@synopsys.com>
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Cc: arc-buildroot@synopsys.com
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/binutils/Config.in.host

@@ -22,7 +22,7 @@ endchoice
 
 config BR2_BINUTILS_VERSION
 	string
-	default "arc-2017.09-rc1"	if BR2_arc
+	default "arc-2017.09-release"	if BR2_arc
 	default "2.27"		if BR2_BINUTILS_VERSION_2_27_X
 	default "2.28.1"	if BR2_BINUTILS_VERSION_2_28_X
 	default "2.29.1"	if BR2_BINUTILS_VERSION_2_29_X

package/binutils/binutils.hash

@@ -4,4 +4,4 @@ sha512	dc5b6872ae01c07c12d38f3bb7ead06effc6da3265ac872e2d9c6104304f89f85f2645b02
 sha512  d748d22306477d60d921078804d21943248c23fca0707aac9b016a352c01c75ca69e82624ae37fb0bbd03af3b17088a94f60dfe1a86a7ff82e18ece3c24f0fd0  binutils-2.29.1.tar.xz
 
 # Locally calculated (fetched from Github)
-sha512  7017056456805c472930a13997e5d5da1031492da7534b09ecaab7c1953ea62513f2c12292c16ec5740acb63493802a30642e28e103919215d0d11e1da997bcb  binutils-arc-2017.09-rc1.tar.gz
+sha512  cefff7521dc4ebd8b9773af4f173821ad82dcb3f1fbd0bfdf03e148ba8cec1262b876b221da628ff5db16c30b18c6cbf5ffbec0fddb4677182524684c4c232c1  binutils-arc-2017.09-release.tar.gz

package/binutils/binutils.mk

@@ -9,7 +9,7 @@
 BINUTILS_VERSION = $(call qstrip,$(BR2_BINUTILS_VERSION))
 ifeq ($(BINUTILS_VERSION),)
 ifeq ($(BR2_arc),y)
-BINUTILS_VERSION = arc-2017.09-rc1
+BINUTILS_VERSION = arc-2017.09-release
 else
 BINUTILS_VERSION = 2.28.1
 endif