Windows, compiling - disable pkg_config

pkg_config usually comes with Strawberry perl, and tends to find packages
that might work in mingw compilation, but not with MSVC.

Thus disable PKG_CONFIG, otherwise any FIND_PACKAGE() that is using PkgConfig
can find something (like LibXml2 from connect), can potentially find something
that is not going to compile.

cmake/os/Windows.cmake

@@ -24,9 +24,6 @@ INCLUDE (CheckCSourceRuns)
 INCLUDE (CheckSymbolExists)
 INCLUDE (CheckTypeSize)
 
-# Optionally read user configuration, generated by configure.js.
-# This is left for backward compatibility reasons only.
-INCLUDE(${CMAKE_BINARY_DIR}/win/configure.data OPTIONAL)
 
 # avoid running system checks by using pre-cached check results
 # system checks are expensive on VS since every tiny program is to be compiled in 
@@ -63,6 +60,8 @@ IF(MINGW AND CMAKE_SIZEOF_VOID_P EQUAL 4)
 ENDIF()
 
 IF(MSVC)
+  # Disable mingw based pkg-config found in Strawberry perl
+  SET(PKG_CONFIG_EXECUTABLE 0 CACHE INTERNAL "")
   SET(MSVC_CRT_TYPE /MT CACHE STRING
     "Runtime library - specify runtime library for linking (/MT,/MTd,/MD,/MDd)"
   )