Merge remote-tracking branch 'remotes/yongbok/tags/mips-20170721' into staging

Merge remote-tracking branch 'remotes/yongbok/tags/mips-20170721' into staging

MIPS patches 2017-07-21

Changes:
* Add Enhanced Virtual Addressing (EVA) support

# gpg: Signature made Fri 21 Jul 2017 03:25:15 BST
# gpg:                using RSA key 0x2238EB86D5F797C2
# gpg: Good signature from "Yongbok Kim <yongbok.kim@imgtec.com>"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 8600 4CF5 3415 A5D9 4CFA  2B5C 2238 EB86 D5F7 97C2

* remotes/yongbok/tags/mips-20170721:
  target/mips: Enable CP0_EBase.WG on MIPS64 CPUs
  target/mips: Add EVA support to P5600
  target/mips: Implement segmentation control
  target/mips: Add segmentation control registers
  target/mips: Add an MMU mode for ERL
  target/mips: Abstract mmu_idx from hflags
  target/mips: Check memory permissions with mem_idx
  target/mips: Decode microMIPS EVA load & store instructions
  target/mips: Decode MIPS32 EVA load & store instructions
  target/mips: Prepare loads/stores for EVA
  target/mips: Add CP0_Ebase.WG (write gate) support
  target/mips: Weaken TLB flush on UX,SX,KX,ASID changes
  target/mips: Fix TLBWI shadow flush for EHINV,XI,RI
  target/mips: Fix MIPS64 MFC0 UserLocal on BE host

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