TCF Agent: add mingw64 cross build support

MinGW uses all lowercase win32 header names and therefore cross
builds on a hosts with a case sensitive filesystem will fail to
lookup the included header.
Use all lowercase for win32 header to have more portable way.

Further guard from macro redefinition as MinGW (superseeded by
MinGW64) uses a quite outdated win32 api definition.

Signed-off-by: Sanimir Agovic <sanimir@subpath.org>
8 files changed