Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20210702' into staging

target-arm queue:
 * more MVE instructions
 * hw/gpio/gpio_pwr: use shutdown function for reboot
 * target/arm: Check NaN mode before silencing NaN
 * tests: Boot and halt a Linux guest on the Raspberry Pi 2 machine
 * hw/arm: Add basic power management to raspi.
 * docs/system/arm: Add quanta-gbs-bmc, quanta-q7l1-bmc

# gpg: Signature made Fri 02 Jul 2021 13:59:19 BST
# gpg:                using RSA key E1A5C593CD419DE28E8315CF3C2525ED14360CDE
# gpg:                issuer "peter.maydell@linaro.org"
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>" [ultimate]
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>" [ultimate]
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>" [ultimate]
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* remotes/pmaydell/tags/pull-target-arm-20210702: (24 commits)
  target/arm: Implement MVE shifts by register
  target/arm: Implement MVE shifts by immediate
  target/arm: Implement MVE long shifts by register
  target/arm: Implement MVE long shifts by immediate
  target/arm: Implement MVE VADDLV
  target/arm: Implement MVE VSHLC
  target/arm: Implement MVE saturating narrowing shifts
  target/arm: Implement MVE VSHRN, VRSHRN
  target/arm: Implement MVE VSRI, VSLI
  target/arm: Implement MVE VSHLL
  target/arm: Implement MVE vector shift right by immediate insns
  target/arm: Implement MVE vector shift left by immediate insns
  target/arm: Implement MVE logical immediate insns
  target/arm: Use dup_const() instead of bitfield_replicate()
  target/arm: Use asimd_imm_const for A64 decode
  target/arm: Make asimd_imm_const() public
  target/arm: Fix bugs in MVE VRMLALDAVH, VRMLSLDAVH
  target/arm: Fix MVE widening/narrowing VLDR/VSTR offset calculation
  hw/gpio/gpio_pwr: use shutdown function for reboot
  target/arm: Check NaN mode before silencing NaN
  ...

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