Remove direct include of `folly/folly-config.h`

Summary: `folly/portability/Config.h` serves this purpose now. Clean up references

Reviewed By: Orvid

Differential Revision: D18800127

fbshipit-source-id: 8e1300af74d63f028b83f5e2d8963a674e77e573

folly/io/async/EventFDWrapper.h

@@ -21,13 +21,7 @@
 
 #pragma once
 
-#ifndef FOLLY_NO_CONFIG
-#include <folly/folly-config.h>
-#endif
-
-#if __has_include(<features.h>)
-#include <features.h>
-#endif
+#include <folly/portability/Config.h>
 
 #if defined(__GLIBC__) && !defined(__APPLE__)
 #if __GLIBC_PREREQ(2, 9)

folly/io/async/SSLContext.h

@@ -26,10 +26,6 @@
 
 #include <glog/logging.h>
 
-#ifndef FOLLY_NO_CONFIG
-#include <folly/folly-config.h>
-#endif
-
 #include <folly/Function.h>
 #include <folly/Portability.h>
 #include <folly/Range.h>