Quick & Easy: Build aomenc Windows build under Ubuntu

compile av1 video codec for windows

• apt update -y && apt install -y build-essential make mingw-w64 yasm cmake git
• git clone https://aomedia.googlesource.com/aom && cd aom/build
• cmake ../ -DCMAKE_TOOLCHAIN_FILE=cmake/toolchains/x86_64-mingw-gcc.cmake -DCMAKE_BUILD_TYPE=Release -DAOM_EXTRA_C_FLAGS=-static -DAOM_EXTRA_CXX_FLAGS=-static -DENABLE_DOCS=0 -DENABLE_TESTS=0 -DCONFIG_AV1_DECODER=0
• make -j$(grep -c ^processor /proc/cpuinfo)