message: build: pass _WIN32_WINNT=0x0601 when building libevent for Windows
  This enables of the use of AI_* definitions in the Windows headers,
  specifically AI_ADDRCONFIG, which fixes an issue with libevent and
  ipv6 on Windows.
  It also aligns with what we define in configure when building Core.
diff: @@ -10,12 +10,16 @@ define $(package)_preprocess_cmds
  ./autogen.sh
  endef
  +# When building for Windows, we set _WIN32_WINNT to target the same Windows
  +# version as we do in configure. Due to quirks in libevents build system, this
  +# is also required to enable support for ipv6. See #19375.
  define $(package)_set_vars
  $(package)_config_opts=--disable-shared --disable-openssl --disable-libevent-regress --disable-samples
  $(package)_config_opts += --disable-dependency-tracking --enable-option-checking
  $(package)_config_opts_release=--disable-debug-mode
  $(package)_config_opts_linux=--with-pic
  $(package)_config_opts_android=--with-pic
  + $(package)_cppflags_mingw32=-D_WIN32_WINNT=0x0601
  endef
  define $(package)_config_cmds
  