Re-add CMAKE_INTERPROCEDURAL_OPTIMIZATION=ON on windows

Author: fdintino

winbuild/build_prepare.py

@@ -399,6 +399,7 @@ def cmd_msbuild(
                 "-DAVIF_CODEC_AOM_DECODE=OFF",
                 "-DAVIF_CODEC_DAV1D=LOCAL",
                 "-DCMAKE_POLICY_VERSION_MINIMUM=3.5",
+                "-DCMAKE_INTERPROCEDURAL_OPTIMIZATION=ON",
                 build_type="MinSizeRel",
             ),
             cmd_xcopy("include", "{inc_dir}"),