Merge tag 'arc-updates-for-2018.09-rc2' of git://git.denx.de/u-boot-arc

That's a set of prety minor changes and fixes for ARC.

Among them:
 * Improvement in CREG GPIO driver used on ARC dev boards
   that allow us to re-use the driver for SPI's chip select

 * Enable SPI-flsh on AXS10x boards which allows to update
   U-Boot binary that gets loaded by boot-ROM

 * Fix accommodating always utilized unaligned access by
   GCC for ARC starting from 8.1.0