Merge remote-tracking branch 'remotes/mcayland/tags/qemu-sparc-20210505' into staging

qemu-sparc queue

# gpg: Signature made Wed 05 May 2021 08:29:13 BST
# gpg:                using RSA key CC621AB98E82200D915CC9C45BC2C56FAE0F321F
# gpg:                issuer "mark.cave-ayland@ilande.co.uk"
# gpg: Good signature from "Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>" [full]
# Primary key fingerprint: CC62 1AB9 8E82 200D 915C  C9C4 5BC2 C56F AE0F 321F

* remotes/mcayland/tags/qemu-sparc-20210505:
  hw/sparc*: Move cpu_check_irqs() to target/sparc/
  hw/sparc64: Fix code style for checkpatch.pl
  hw/sparc64: Remove unused "hw/char/serial.h" header
  hw/sparc: Allow building without the leon3 machine
  hw/sparc/sun4m: Move each sun4m_hwdef definition in its class_init
  hw/sparc/sun4m: Fix code style for checkpatch.pl
  hw/sparc/sun4m: Register machine types in sun4m_machine_types[]
  hw/sparc/sun4m: Factor out sun4m_machine_class_init()
  hw/sparc/sun4m: Introduce Sun4mMachineClass
  hw/sparc/sun4m: Have sun4m machines inherit new TYPE_SUN4M_MACHINE

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