CLEANUP: includes: fix includes for a number of users of fd.h
It appears that fd.h includes a number of unneeded files and was
included from standard.h, and as such served as an intermediary
to provide almost everything to everyone.
By removing its useless includes, a long dependency chain broke
but could easily be fixed.
diff --git a/src/standard.c b/src/standard.c
index 0af7c95..e7bc070 100644
--- a/src/standard.c
+++ b/src/standard.c
@@ -13,6 +13,7 @@
#include <ctype.h>
#include <netdb.h>
#include <stdarg.h>
+#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>