Merge remote-tracking branch 'remotes/armbru/tags/pull-error-2018-02-06' into staging

Error reporting patches for 2018-02-06

# gpg: Signature made Tue 06 Feb 2018 19:48:30 GMT
# gpg:                using RSA key 3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-error-2018-02-06:
  tcg: Replace fprintf(stderr, "*\n" with error_report()
  hw/xen*: Replace fprintf(stderr, "*\n" with error_report()
  hw/sparc*: Replace fprintf(stderr, "*\n" with error_report()
  hw/sd: Replace fprintf(stderr, "*\n" with DPRINTF()
  hw/ppc: Replace fprintf(stderr, "*\n" with error_report()
  hw/pci*: Replace fprintf(stderr, "*\n" with error_report()
  hw/openrisc: Replace fprintf(stderr, "*\n" with error_report()
  hw/moxie: Replace fprintf(stderr, "*\n" with error_report()
  hw/mips: Replace fprintf(stderr, "*\n" with error_report()
  hw/lm32: Replace fprintf(stderr, "*\n" with error_report()
  hw/dma: Replace fprintf(stderr, "*\n" with error_report()
  hw/arm: Replace fprintf(stderr, "*\n" with error_report()
  audio: Replace AUDIO_FUNC with __func__
  error: Improve documentation of error_append_hint()

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