powerpc/boot: Parse chosen/cmdline-timeout parameter

On some platforms a 5 second timeout during boot might be quite long, so
make it configurable. Run the loop at least once to let the user stop
the boot by holding a key pressed. If the timeout is set to 0, don't
wait for input, which can be used as a workaround if the boot hangs on
random data coming in on the serial port.

Signed-off-by: Simon Kagstrom <simon.kagstrom@netinsight.net>
[mpe: Changelog wording & whitespace]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/arch/powerpc/boot/ops.h b/arch/powerpc/boot/ops.h
index 8aad3c5..5e75e1c 100644
--- a/arch/powerpc/boot/ops.h
+++ b/arch/powerpc/boot/ops.h
@@ -58,7 +58,7 @@
 struct console_ops {
 	int	(*open)(void);
 	void	(*write)(const char *buf, int len);
-	void	(*edit_cmdline)(char *buf, int len);
+	void	(*edit_cmdline)(char *buf, int len, unsigned int getline_timeout);
 	void	(*close)(void);
 	void	*data;
 };