include: Add the msvcrt/crtdefs.h header and include it where needed.

include/Makefile.in

diff --git a/include/Makefile.in b/include/Makefile.in
index 5b24e0d..abb89ab 100644
--- a/include/Makefile.in
+++ b/include/Makefile.in
@@ -290,6 +290,7 @@
 	mstcpip.h \
 	msvcrt/conio.h \
 	msvcrt/crtdbg.h \
+	msvcrt/crtdefs.h \
 	msvcrt/ctype.h \
 	msvcrt/direct.h \
 	msvcrt/dirent.h \