Merge remote-tracking branch 'remotes/riku/tags/pull-linux-user-20150323' into staging

Merge remote-tracking branch 'remotes/riku/tags/pull-linux-user-20150323' into staging

linux-user patches for 2.3-rc1

# gpg: Signature made Mon Mar 23 13:51:56 2015 GMT using RSA key ID DE3C9BC0
# gpg: Good signature from "Riku Voipio <riku.voipio@iki.fi>"
# gpg:                 aka "Riku Voipio <riku.voipio@linaro.org>"

* remotes/riku/tags/pull-linux-user-20150323:
  linux-user: fix broken cpu_copy()
  linux-user: fix emulation of splice syscall
  linux-user/main.c: Remove redundant end_exclusive() in arm_kernel_cmpxchg64_helper()

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