is_computer_on() lives again as a true syscall.

Replaced the _kern_null syscall with _kern_is_computer_on.
is_computer_on_fire is a bit harder, since it returns a float from kernelland, which
at the moment isn't supported in haiku.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@20069 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/private/kernel/syscalls.h

@@ -43,7 +43,7 @@ struct user_disk_system_info;
 #pragma syscalls begin
 #endif
 
-extern int     		_kern_null();
+extern int			_kern_is_computer_on(void);
 extern status_t		_kern_generic_syscall(const char *subsystem, uint32 function,
 						void *buffer, size_t bufferSize);