Pull xtensa updates from Max Filippov:

 - implement atomic operations using exclusive access Xtensa option
   operations

 - add support for Xtensa cores with memory protection unit (MPU)

 - clean up xtensa-specific kernel-only headers

 - fix error path in simdisk_setup

* tag 'xtensa-20190510' of git://github.com/jcmvbkbc/linux-xtensa:
  xtensa: implement initialize_cacheattr for MPU cores
  xtensa: add exclusive atomics support
  xtensa: clean up inline assembly in futex.h
  xtensa: replace variant/core.h with asm/core.h
  xtensa: drop ifdef __KERNEL__ from kernel-only headers
  xtensa: set proper error code for simdisk_setup()
  xtensa: fix incorrect fd close in error case of simdisk_setup()