Merge remote-tracking branch 'remotes/philmd-gitlab/tags/mips-fixes-20201103' into staging

MIPS patches queue

- Removal of the 'r4k' machine (deprecated before 5.0)
- Fix LGPL license text (Chetan Pant)
- Support unaligned accesses on Loongson-3 (Huacai Chen)
- Fix out-of-bound access in Loongson-3 embedded I/O interrupt
  controller (Alex Chen)

CI jobs results:
. https://cirrus-ci.com/build/6324890389184512
. https://gitlab.com/philmd/qemu/-/pipelines/211275262
. https://travis-ci.org/github/philmd/qemu/builds/741188958



# gpg: Signature made Tue 03 Nov 2020 17:30:30 GMT
# gpg:                using RSA key FAABE75E12917221DCFD6BB2E3E32C2CDEADC0DE
# gpg: Good signature from "Philippe Mathieu-Daudé (F4BUG) <f4bug@amsat.org>" [full]
# Primary key fingerprint: FAAB E75E 1291 7221 DCFD  6BB2 E3E3 2C2C DEAD C0DE

* remotes/philmd-gitlab/tags/mips-fixes-20201103:
  target/mips: Add unaligned access support for MIPS64R6 and Loongson-3
  target/mips: Fix Lesser GPL version number
  hw/intc/loongson: Fix incorrect 'core' calculation in liointc_read/write
  hw/mips/boston: Fix Lesser GPL version number
  hw/mips: Fix Lesser GPL version number
  hw/mips: Remove the 'r4k' machine

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