<unistd.h> __INTRODUCED_IN cleaup.

The NDK doesn't support anything older than API level 16, so remove some
more clutter.

Test: builds
Change-Id: If257a27841396af001b089b7ae0fbd8c3e0128e4
diff --git a/libc/include/bits/fortify/unistd.h b/libc/include/bits/fortify/unistd.h
index 547a168..c42bd0c 100644
--- a/libc/include/bits/fortify/unistd.h
+++ b/libc/include/bits/fortify/unistd.h
@@ -35,14 +35,13 @@
 ssize_t __pread_real(int, void*, size_t, off_t) __RENAME(pread);
 
 ssize_t __pread64_chk(int, void*, size_t, off64_t, size_t) __INTRODUCED_IN(23);
-ssize_t __pread64_real(int, void*, size_t, off64_t) __RENAME(pread64) __INTRODUCED_IN(12);
+ssize_t __pread64_real(int, void*, size_t, off64_t) __RENAME(pread64);
 
 ssize_t __pwrite_chk(int, const void*, size_t, off_t, size_t) __INTRODUCED_IN(24);
 ssize_t __pwrite_real(int, const void*, size_t, off_t) __RENAME(pwrite);
 
 ssize_t __pwrite64_chk(int, const void*, size_t, off64_t, size_t) __INTRODUCED_IN(24);
-ssize_t __pwrite64_real(int, const void*, size_t, off64_t) __RENAME(pwrite64)
-  __INTRODUCED_IN(12);
+ssize_t __pwrite64_real(int, const void*, size_t, off64_t) __RENAME(pwrite64);
 
 ssize_t __read_chk(int, void*, size_t, size_t) __INTRODUCED_IN(21);
 ssize_t __write_chk(int, const void*, size_t, size_t) __INTRODUCED_IN(24);
diff --git a/libc/include/unistd.h b/libc/include/unistd.h
index 9766b36..7c01549 100644
--- a/libc/include/unistd.h
+++ b/libc/include/unistd.h
@@ -204,7 +204,7 @@
 long pathconf(const char* __path, int __name);
 
 int access(const char* __path, int __mode);
-int faccessat(int __dirfd, const char* __path, int __mode, int __flags) __INTRODUCED_IN(16);
+int faccessat(int __dirfd, const char* __path, int __mode, int __flags);
 int link(const char* __old_path, const char* __new_path);
 int linkat(int __old_dir_fd, const char* __old_path, int __new_dir_fd, const char* __new_path, int __flags) __INTRODUCED_IN(21);
 int unlink(const char* __path);
@@ -248,11 +248,9 @@
 #if defined(__USE_FILE_OFFSET64)
 int truncate(const char* __path, off_t __length) __RENAME(truncate64) __INTRODUCED_IN(21);
 off_t lseek(int __fd, off_t __offset, int __whence) __RENAME(lseek64);
-ssize_t pread(int __fd, void* __buf, size_t __count, off_t __offset)
-  __RENAME(pread64) __INTRODUCED_IN(12);
-ssize_t pwrite(int __fd, const void* __buf, size_t __count, off_t __offset)
-  __RENAME(pwrite64) __INTRODUCED_IN(12);
-int ftruncate(int __fd, off_t __length) __RENAME(ftruncate64) __INTRODUCED_IN(12);
+ssize_t pread(int __fd, void* __buf, size_t __count, off_t __offset) __RENAME(pread64);
+ssize_t pwrite(int __fd, const void* __buf, size_t __count, off_t __offset) __RENAME(pwrite64);
+int ftruncate(int __fd, off_t __length) __RENAME(ftruncate64);
 #else
 int truncate(const char* __path, off_t __length);
 off_t lseek(int __fd, off_t __offset, int __whence);
@@ -263,9 +261,9 @@
 
 int truncate64(const char* __path, off64_t __length) __INTRODUCED_IN(21);
 off64_t lseek64(int __fd, off64_t __offset, int __whence);
-ssize_t pread64(int __fd, void* __buf, size_t __count, off64_t __offset) __INTRODUCED_IN(12);
-ssize_t pwrite64(int __fd, const void* __buf, size_t __count, off64_t __offset) __INTRODUCED_IN(12);
-int ftruncate64(int __fd, off64_t __length) __INTRODUCED_IN(12);
+ssize_t pread64(int __fd, void* __buf, size_t __count, off64_t __offset);
+ssize_t pwrite64(int __fd, const void* __buf, size_t __count, off64_t __offset);
+int ftruncate64(int __fd, off64_t __length);
 
 int pause(void);
 unsigned int alarm(unsigned int __seconds);