Make some of the fcntl flags arch specific..

Some of the flags in the file system related system call
are architecture specific(O_NOFOLLOW/O_DIRECT..). Ref to
the fcntl.h file in the Linux src codes.

Signed-off-by: Haibo Xu <haibo.xu@arm.com>
Change-Id: I354d988073bfd0c9ff5371d4e0be9da2b8fd019f

pkg/abi/linux/file.go

@@ -24,27 +24,23 @@ import (
 
 // Constants for open(2).
 const (
-	O_ACCMODE   = 000000003
-	O_RDONLY    = 000000000
-	O_WRONLY    = 000000001
-	O_RDWR      = 000000002
-	O_CREAT     = 000000100
-	O_EXCL      = 000000200
-	O_NOCTTY    = 000000400
-	O_TRUNC     = 000001000
-	O_APPEND    = 000002000
-	O_NONBLOCK  = 000004000
-	O_DSYNC     = 000010000
-	O_ASYNC     = 000020000
-	O_DIRECT    = 000040000
-	O_LARGEFILE = 000100000
-	O_DIRECTORY = 000200000
-	O_NOFOLLOW  = 000400000
-	O_NOATIME   = 001000000
-	O_CLOEXEC   = 002000000
-	O_SYNC      = 004000000 // __O_SYNC in Linux
-	O_PATH      = 010000000
-	O_TMPFILE   = 020000000 // __O_TMPFILE in Linux
+	O_ACCMODE  = 000000003
+	O_RDONLY   = 000000000
+	O_WRONLY   = 000000001
+	O_RDWR     = 000000002
+	O_CREAT    = 000000100
+	O_EXCL     = 000000200
+	O_NOCTTY   = 000000400
+	O_TRUNC    = 000001000
+	O_APPEND   = 000002000
+	O_NONBLOCK = 000004000
+	O_DSYNC    = 000010000
+	O_ASYNC    = 000020000
+	O_NOATIME  = 001000000
+	O_CLOEXEC  = 002000000
+	O_SYNC     = 004000000 // __O_SYNC in Linux
+	O_PATH     = 010000000
+	O_TMPFILE  = 020000000 // __O_TMPFILE in Linux
 )
 
 // Constants for fstatat(2).

pkg/abi/linux/file_amd64.go

@@ -14,6 +14,14 @@
 
 package linux
 
+// Constants for open(2).
+const (
+	O_DIRECT    = 000040000
+	O_LARGEFILE = 000100000
+	O_DIRECTORY = 000200000
+	O_NOFOLLOW  = 000400000
+)
+
 // Stat represents struct stat.
 type Stat struct {
 	Dev     uint64

pkg/abi/linux/file_arm64.go

@@ -14,6 +14,14 @@
 
 package linux
 
+// Constants for open(2).
+const (
+	O_DIRECTORY = 000040000
+	O_NOFOLLOW  = 000100000
+	O_DIRECT    = 000200000
+	O_LARGEFILE = 000400000
+)
+
 // Stat represents struct stat.
 type Stat struct {
 	Dev     uint64