【libxml2】v162 x64 MT build, including dependent library libiconv

• It is necessary to build a MT version with a static runtime library and an x64 xml2 library.
• Found to depend on iconv
• Download libmxl2, address

libiconv-win-build 1.17

• The master's project on github is much more convenient than the official one and can be built directly
• Officially we need to do nmake

cmake build libiconv-static.lib

Found Iconv: G:/DEV/live-player/RTCPLAYER/CicadaPlayerNBS_MT/3rdparty/libiconv-win-build/build-VS2019-MT/x64/Release/libiconv-static.lib (found version "1.17") 
Checking for module 'liblzma'
  Found liblzma, version 5.2.4
Performi