Remove __INTRODUCED_IN for obsolete API levels.

The NDK only supports >= 16, so remove anything older than that to avoid
giving the misleading impression that such old targets are still
supported.

(This change doesn't touch <unistd.h>. I'll follow up with that once the
outstanding FORTIFY changes to that file are in.)

Test: builds
Change-Id: I6cc6ecdb99fe228a4afa71f78e5fd45309ba9786
diff --git a/libc/include/fenv.h b/libc/include/fenv.h
index 886612e..90ac805 100644
--- a/libc/include/fenv.h
+++ b/libc/include/fenv.h
@@ -46,11 +46,9 @@
 // fenv was always available on x86.
 #if __ANDROID_API__ >= __ANDROID_API_L__ || defined(__i386__)
 int feclearexcept(int __exceptions) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21) __INTRODUCED_IN_X86(9);
-int fegetexceptflag(fexcept_t* __flag_ptr, int __exceptions) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21)
-    __INTRODUCED_IN_X86(9);
+int fegetexceptflag(fexcept_t* __flag_ptr, int __exceptions) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21) __INTRODUCED_IN_X86(9);
 int feraiseexcept(int __exceptions) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21) __INTRODUCED_IN_X86(9);
-int fesetexceptflag(const fexcept_t* __flag_ptr, int __exceptions) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21)
-    __INTRODUCED_IN_X86(9);
+int fesetexceptflag(const fexcept_t* __flag_ptr, int __exceptions) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21) __INTRODUCED_IN_X86(9);
 int fetestexcept(int __exceptions) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21) __INTRODUCED_IN_X86(9);
 
 int fegetround(void) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21) __INTRODUCED_IN_X86(9);
@@ -59,8 +57,7 @@
 int fegetenv(fenv_t* __env) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21) __INTRODUCED_IN_X86(9);
 int feholdexcept(fenv_t* __env) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21) __INTRODUCED_IN_X86(9);
 int fesetenv(const fenv_t* __env) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21) __INTRODUCED_IN_X86(9);
-int feupdateenv(const fenv_t* __env) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21)
-    __INTRODUCED_IN_X86(9);
+int feupdateenv(const fenv_t* __env) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21) __INTRODUCED_IN_X86(9);
 
 int feenableexcept(int __exceptions) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21) __INTRODUCED_IN_X86(9);
 int fedisableexcept(int __exceptions) __INTRODUCED_IN_ARM(21) __INTRODUCED_IN_MIPS(21) __INTRODUCED_IN_X86(9);