pkg-config windows installation, not able to find libxml-2.0

Question

I am trying to install github.com/terminalstatic/go-xsd-validate for xsd validation and have followed the steps mentioned in the link - https://medium.com/@kumarharsh/using-libxml2-headers-in-windows-5d548077cde5

1. My pkg-config.exe is in C:\Users\..\go\bin
2. Environment Variable PKG_CONFIG_PATH is set to C:\mysys64\usr\lib\pkgconfig
3. libxml-2.0.pc file is present at the above path
4. Running which gcc gives: /usr/bin/gcc

go get github.com/terminalstatic/go-xsd-validate

Receiving this error:

pkg-config --cflags  -- libxml-2.0
Package libxml-2.0 was not found in the pkg-config search path.
Perhaps you should add the directory containing `libxml-2.0.pc'
to the PKG_CONFIG_PATH environment variable
No package 'libxml-2.0' found
pkg-config: exit status 1

The entire set up looks very confusing, not sure what I miss in between. ANy hints would be helpful !