Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20200803' into staging

target-arm queue:
 * hw/timer/imx_epit: Avoid assertion when CR.SWR is written
 * netduino2, netduinoplus2, microbit: set system_clock_scale so that
   SysTick running on the CPU clock works
 * target/arm: Avoid maybe-uninitialized warning with gcc 4.9
 * target/arm: Fix AddPAC error indication
 * Make AIRCR.SYSRESETREQ actually reset the system for the
   microbit, mps2-*, musca-*, netduino* boards

# gpg: Signature made Mon 03 Aug 2020 20:29:17 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-20200803:
  hw/timer/imx_epit: Avoid assertion when CR.SWR is written
  hw/arm/nrf51_soc: Set system_clock_scale
  target/arm: Avoid maybe-uninitialized warning with gcc 4.9
  target/arm: Fix AddPAC error indication
  msf2-soc, stellaris: Don't wire up SYSRESETREQ
  hw/intc/armv7m_nvic: Provide default "reset the system" behaviour for SYSRESETREQ
  include/hw/irq.h: New function qemu_irq_is_connected()
  hw/arm/netduino2, netduinoplus2: Set system_clock_scale

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