_FILE_OFFSET_BITS=64 support for fcntl.

On Android, fcntl is always implemented by fcntl64(2). This means that
an LP32 binary can `fcntl(F_SETLK, struct flock)` (because fcntl64(2)
passes through to the 32-bit fcntl(2) to handle F_SETLK), and it can
also `fcntl(F_SETLK64, struct flock64)`. What it can't do before this
patch is set _FILE_OFFSET_BITS=64 and then `fcntl(F_SETLK, struct
flock)` where that `struct flock` is actually implicitly `struct
flock64`.

Move the kernel uapi structs out of the way, define them ourselves based
on __LP64__ and _FILE_OFFSET_BITS, and fix up the relevant F_ constants.

(Also add a .clang-format to turn off clang-format in libc/include/.)

Bug: N/A
Test: treehugger (and strace!)
Change-Id: Iccd6c83d9133e1efcf93a7b49a6ae0f1bbd3d58b
diff --git a/libc/kernel/tools/defaults.py b/libc/kernel/tools/defaults.py
index 967d0c7..463de12 100644
--- a/libc/kernel/tools/defaults.py
+++ b/libc/kernel/tools/defaults.py
@@ -90,6 +90,8 @@
 kernel_struct_replacements = set(
         [
           "epoll_event",
+          "flock",
+          "flock64",
           "in_addr",
           "ip_mreq_source",
           "ip_msfilter",
diff --git a/libc/kernel/uapi/asm-generic/fcntl.h b/libc/kernel/uapi/asm-generic/fcntl.h
index aeb1ac6..a2cb5f4 100644
--- a/libc/kernel/uapi/asm-generic/fcntl.h
+++ b/libc/kernel/uapi/asm-generic/fcntl.h
@@ -18,6 +18,8 @@
  ****************************************************************************/
 #ifndef _ASM_GENERIC_FCNTL_H
 #define _ASM_GENERIC_FCNTL_H
+#include <bits/flock64.h>
+#include <bits/flock.h>
 #include <linux/types.h>
 #define O_ACCMODE 00000003
 #define O_RDONLY 00000000
@@ -145,26 +147,10 @@
 #ifndef __ARCH_FLOCK_PAD
 #define __ARCH_FLOCK_PAD
 #endif
-struct flock {
-  short l_type;
-  short l_whence;
-  __kernel_off_t l_start;
-  __kernel_off_t l_len;
-  __kernel_pid_t l_pid;
-  __ARCH_FLOCK_PAD
-};
 #endif
 #ifndef HAVE_ARCH_STRUCT_FLOCK64
 #ifndef __ARCH_FLOCK64_PAD
 #define __ARCH_FLOCK64_PAD
 #endif
-struct flock64 {
-  short l_type;
-  short l_whence;
-  __kernel_loff_t l_start;
-  __kernel_loff_t l_len;
-  __kernel_pid_t l_pid;
-  __ARCH_FLOCK64_PAD
-};
 #endif
 #endif
diff --git a/libc/kernel/uapi/asm-mips/asm/fcntl.h b/libc/kernel/uapi/asm-mips/asm/fcntl.h
index 91835f2..8aef90d 100644
--- a/libc/kernel/uapi/asm-mips/asm/fcntl.h
+++ b/libc/kernel/uapi/asm-mips/asm/fcntl.h
@@ -18,6 +18,7 @@
  ****************************************************************************/
 #ifndef _UAPI_ASM_FCNTL_H
 #define _UAPI_ASM_FCNTL_H
+#include <bits/flock.h>
 #include <asm/sgidefs.h>
 #define O_APPEND 0x0008
 #define O_DSYNC 0x0010
@@ -43,15 +44,6 @@
 #endif
 #if _MIPS_SIM != _MIPS_SIM_ABI64
 #include <linux/types.h>
-struct flock {
-  short l_type;
-  short l_whence;
-  __kernel_off_t l_start;
-  __kernel_off_t l_len;
-  long l_sysid;
-  __kernel_pid_t l_pid;
-  long pad[4];
-};
 #define HAVE_ARCH_STRUCT_FLOCK
 #endif
 #include <asm-generic/fcntl.h>