Make it possible to build a DLL without DllMain

[ghost]

This is possible with GCC compiler.

[GitMensch]

This is also possible with MSVC and OrangeC, just compile. Do you have an error which shows different?

[ghost]

His answer here confused me: #981 (comment)

for a dll do this:

occ -Wd testprog.c

and here you need DllMain

This implied that I need DllMain.

[LADSoft]

so I misspoke, what I probably should have said is if you need a main use DllMain(). I did check a minute ago, OrangeC is quite happy making a DLL if you don't explicitly add a DllMain().