[Build][Windows] Add windows debug postfix definition

Author: enen92

src/CMakeLists.txt

@@ -236,6 +236,7 @@ if(WIN32)
   target_compile_definitions(exiv2lib PRIVATE PSAPI_VERSION=1) # to be compatible with <= WinVista (#905)
   # Since windows.h is included in some headers, we need to propagate this definition
   target_compile_definitions(exiv2lib PUBLIC WIN32_LEAN_AND_MEAN)
+  set_target_properties(exiv2lib PROPERTIES DEBUG_POSTFIX d)
 endif()
 
 if(NOT MSVC)