bits/ioctl.h: add TIOC{G,S}ISO7816 from linux v4.20

ISO7816 smart cards ioctls.
linux commit ad8c0eaa0a418ae8ef3f9217638bb86439399eac

the actual kernel definitions are

 #define TIOCGISO7816 _IOR('T', 0x42, struct serial_iso7816)
 #define TIOCSISO7816 _IOWR('T', 0x43, struct serial_iso7816)

where struct serial_iso7816 is defined in linux/serial.h as

struct serial_iso7816 {
	__u32   flags;
	__u32   tg;
	__u32   sc_fi;
	__u32   sc_di;
	__u32   clk;
	__u32   reserved[5];
};

arch/generic/bits/ioctl.h

@@ -64,6 +64,8 @@
 #define TIOCGPTLCK	0x80045439
 #define TIOCGEXCL	0x80045440
 #define TIOCGPTPEER	0x5441
+#define TIOCGISO7816	0x80285442
+#define TIOCSISO7816	0xc0285443
 
 #define FIONCLEX	0x5450
 #define FIOCLEX		0x5451