testing and plugin updates for 7.2: - cleanup win32/64 docker files - update test-mingw test - add flex/bison to debian-all-test - handle --enable-static/--disable-pie in config - extend timeouts on x86_64 avocado tests - add flex/bison to debian-hexagon-cross - use regular semihosting for nios2 check-tcg - fix obscure linker error to nios2 softmmu tests - various windows portability fixes for tests - clean-up of MAINTAINERS - use -machine none when appropriate in avocado - make raspi2_initrd test detect shutdown - disable sh4 rd2 tests on gitlab - re-enable threadcount/linux-test for sh4 - clean-up s390x handling of "ex" instruction - better handle new CPUs in execlog plugin - pass CONFIG_DEBUG_TCG to plugin builds - try and avoid races in test-io-channel-command - speed up ssh key checking for tests/vm