GitLab

 lib-src/makefile.w32-in ($(BLD)/emacsclientw.exe): Use $(MWINDOWS)
 instead of a literal -mwindows, which is not supported by MSVC.
 nt/nmake.defs (MWINDOWS): Define as "-subsystem:windows -entry:mainCRTStartup".
 Suggested by Fabrice Popineau <fabrice.popineau@supelec.fr>.
 nt/gmake.defs (MWINDOWS): Define as "-mwindows".