scripts: gha: win32: finally use destdir instead of prefix on Windows

scripts/gha/build_win32.sh

@@ -11,9 +11,9 @@ fi
 
 # NOTE: to build with other version use --msvc_version during configuration
 # NOTE: sometimes you may need to add WinSDK to %PATH%
-./waf.bat configure -s "SDL2_VC" -T "release" --enable-utils --enable-tests --prefix=`pwd` $AMD64 || die_configure
+./waf.bat configure -s "SDL2_VC" -T "release" --enable-utils --enable-tests $AMD64 || die_configure
 ./waf.bat build || die
-./waf.bat install || die
+./waf.bat install --destdir=. || die
 
 if [ "$ARCH" = "i386" ]; then
 	cp SDL2_VC/lib/x86/SDL2.dll . # Install SDL2