Remove unnecessary 'extern's.

Change-Id: Iba2b3fb6ff88e504f1657b915120ae43d58a1e03
diff --git a/libc/include/sys/stat.h b/libc/include/sys/stat.h
index a65f27a..4397a0d 100644
--- a/libc/include/sys/stat.h
+++ b/libc/include/sys/stat.h
@@ -141,24 +141,24 @@
 #define S_IEXEC S_IXUSR
 #endif
 
-extern int chmod(const char*, mode_t);
-extern int fchmod(int, mode_t);
-extern int mkdir(const char*, mode_t);
+int chmod(const char*, mode_t);
+int fchmod(int, mode_t);
+int mkdir(const char*, mode_t);
 
-extern int fstat(int, struct stat*);
-extern int fstat64(int, struct stat64*) __INTRODUCED_IN(21);
-extern int fstatat(int, const char*, struct stat*, int);
-extern int fstatat64(int, const char*, struct stat64*, int) __INTRODUCED_IN(21);
-extern int lstat(const char*, struct stat*);
-extern int lstat64(const char*, struct stat64*) __INTRODUCED_IN(21);
-extern int stat(const char*, struct stat*);
-extern int stat64(const char*, struct stat64*) __INTRODUCED_IN(21);
+int fstat(int, struct stat*);
+int fstat64(int, struct stat64*) __INTRODUCED_IN(21);
+int fstatat(int, const char*, struct stat*, int);
+int fstatat64(int, const char*, struct stat64*, int) __INTRODUCED_IN(21);
+int lstat(const char*, struct stat*);
+int lstat64(const char*, struct stat64*) __INTRODUCED_IN(21);
+int stat(const char*, struct stat*);
+int stat64(const char*, struct stat64*) __INTRODUCED_IN(21);
 
-extern int mknod(const char*, mode_t, dev_t);
-extern mode_t umask(mode_t);
+int mknod(const char*, mode_t, dev_t);
+mode_t umask(mode_t);
 
-extern mode_t __umask_chk(mode_t) __INTRODUCED_IN(18);
-extern mode_t __umask_real(mode_t) __RENAME(umask);
+mode_t __umask_chk(mode_t) __INTRODUCED_IN(18);
+mode_t __umask_real(mode_t) __RENAME(umask);
 __errordecl(__umask_invalid_mode, "umask called with invalid mode");
 
 #if defined(__BIONIC_FORTIFY)
@@ -183,17 +183,17 @@
 // Implemented as a static inline before 21.
 #endif
 
-extern int mkfifoat(int, const char*, mode_t) __INTRODUCED_IN(23);
+int mkfifoat(int, const char*, mode_t) __INTRODUCED_IN(23);
 
-extern int fchmodat(int, const char*, mode_t, int);
-extern int mkdirat(int, const char*, mode_t);
-extern int mknodat(int, const char*, mode_t, dev_t) __INTRODUCED_IN(21);
+int fchmodat(int, const char*, mode_t, int);
+int mkdirat(int, const char*, mode_t);
+int mknodat(int, const char*, mode_t, dev_t) __INTRODUCED_IN(21);
 
 #define UTIME_NOW  ((1L << 30) - 1L)
 #define UTIME_OMIT ((1L << 30) - 2L)
-extern int utimensat(int fd, const char* path, const struct timespec times[2], int flags)
+int utimensat(int fd, const char* path, const struct timespec times[2], int flags)
   __INTRODUCED_IN(12);
-extern int futimens(int fd, const struct timespec times[2]) __INTRODUCED_IN(19);
+int futimens(int fd, const struct timespec times[2]) __INTRODUCED_IN(19);
 
 __END_DECLS