Merge remote-tracking branch 'remotes/xtensa/tags/20180122-xtensa' into staging

Merge remote-tracking branch 'remotes/xtensa/tags/20180122-xtensa' into staging

target/xtensa updates:

- make mini-bootloader independent of the initial CPU state;
- add noMMU XTFPGA variants;
- add two noMMU cores: de212 and sample_controller;
- fix issues reported by coverity against xtensa translator and disassembler.

# gpg: Signature made Mon 22 Jan 2018 20:00:01 GMT
# gpg:                using RSA key 0x51F9CC91F83FA044
# gpg: Good signature from "Max Filippov <filippov@cadence.com>"
# gpg:                 aka "Max Filippov <max.filippov@cogentembedded.com>"
# gpg:                 aka "Max Filippov <jcmvbkbc@gmail.com>"
# Primary key fingerprint: 2B67 854B 98E5 327D CDEB  17D8 51F9 CC91 F83F A044

* remotes/xtensa/tags/20180122-xtensa:
  target/xtensa: disas/xtensa: fix coverity warnings
  target/xtensa: add sample_controller core
  target/xtensa: allow different default CPU for MMU/noMMU
  target/xtensa: add de212 core
  hw/xtensa/xtfpga: support noMMU cores
  hw/xtensa/xtfpga: extract flash configuration
  hw/xtensa: extract xtensa_create_memory_regions
  target/xtensa: fix default sysrom/sysram addresses
  hw/xtensa/xtfpga: clean up function/structure names
  hw/xtensa/xtfpga: rewrite mini bootloader

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>