Mark arguments to certain syscalls as being const

Mark arguments to certain system calls as being const where they should be but
aren't.  The list includes:

 (*) The filename arguments of various stat syscalls, execve(), various utimes
     syscalls and some mount syscalls.

 (*) The filename arguments of some syscall helpers relating to the above.

 (*) The buffer argument of various write syscalls.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/m68k/kernel/process.c

@@ -315,7 +315,7 @@ EXPORT_SYMBOL(dump_fpu);
 /*
  * sys_execve() executes a new program.
  */
-asmlinkage int sys_execve(char __user *name, char __user * __user *argv, char __user * __user *envp)
+asmlinkage int sys_execve(const char __user *name, char __user * __user *argv, char __user * __user *envp)
 {
 	int error;
 	char * filename;