Put back inline definitions if using an old API.

All these inlines were turned in to out of line definitions in L.
This brings us a step closer to being able to just use the current
bionic headers for the NDK, rather than having many old versions of
them.

Change-Id: Ie010bc727d78d3742abc577c70f6578db2e68625
diff --git a/libc/include/termios.h b/libc/include/termios.h
index b9685ca..683fde2 100644
--- a/libc/include/termios.h
+++ b/libc/include/termios.h
@@ -35,6 +35,7 @@
 
 __BEGIN_DECLS
 
+#if __ANDROID_API__ >= 21
 speed_t cfgetispeed(const struct termios*);
 speed_t cfgetospeed(const struct termios*);
 void cfmakeraw(struct termios*);
@@ -48,6 +49,9 @@
 pid_t tcgetsid(int);
 int tcsendbreak(int, int);
 int tcsetattr(int, int, const struct termios*);
+#else
+#include <android/legacy_termios_inlines.h>
+#endif
 
 __END_DECLS