sh: ap325 camera without i2c driver fix

This patch fixes the ap325rxa ncm03j camera code to handle
the case where no i2c driver is present. Without this fix
i2c_transfer() may be passed NULL as adapter which results
in a crash.

Triggered when i2c-sh_mobile.c failed to probe() due to
missing MSTP clocks.
Signed-off-by: NMagnus Damm <damm@igel.co.jp>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

arch/sh/boards/board-ap325rxa.c

@@ -263,6 +263,9 @@ static int camera_probe(void)
 	struct i2c_msg msg;
 	int ret;
 
+	if (!a)
+		return -ENODEV;
+
 	camera_power(1);
 	msg.addr = 0x6e;
 	msg.buf = camera_ncm03j_magic;