Bump buildroot to 2019.02

bsp/buildroot/board/synopsys/hsdk/readme.txt

@@ -0,0 +1,33 @@
+Synopsys, Inc.
+ARC HS Development Kit (HSDK)
+
+https://embarc.org/platforms.html
+
+How to build it
+===============
+
+Select the default configuration for the target:
+$ make snps_archs38_hsdk_defconfig
+
+Optional: modify the configuration:
+$ make menuconfig
+
+Build:
+$ make
+
+Result of the build
+===================
+output/images/
+├── boot.vfat
+├── rootfs.ext2
+├── sdcard.img
+├── u-boot
+├── u-boot.bin
+├── uboot-env.bin
+└── uImage
+
+To copy the image file to the sdcard use dd:
+$ dd if=output/images/sdcard.img of=/dev/XXX
+
+2018, Evgeniy Didin <Evgeniy.Didin@synopsys.com>
+