Move bootretry code into bootretry.c and clean up

This code is only used by one board, so it seems a shame to clutter up
the readline code with it. Move it into its own file.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/include/bootretry.h b/include/bootretry.h
new file mode 100644
index 0000000..025c29d
--- /dev/null
+++ b/include/bootretry.h
@@ -0,0 +1,31 @@
+/*
+ * (C) Copyright 2000
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __bootretry_h
+#define __bootretry_h
+
+#ifdef CONFIG_BOOT_RETRY_TIME
+/**
+ * bootretry_tstc_timeout() - ensure we get a keypress before timeout
+ *
+ * Check for a keypress repeatedly, resetting the watchdog each time. If a
+ * keypress is not received within the command timeout, return an error.
+ *
+ * @return 0 if a key is received in time, -ETIMEDOUT if not
+ */
+int bootretry_tstc_timeout(void);
+#else
+static inline int bootretry_tstc_timeout(void)
+{
+	return 0;
+}
+#endif
+
+void init_cmd_timeout(void);
+void reset_cmd_timeout(void);
+
+#endif
diff --git a/include/common.h b/include/common.h
index 75cb525..91745cf 100644
--- a/include/common.h
+++ b/include/common.h
@@ -286,8 +286,6 @@
  * @return 0 on success, or != 0 on error.
  */
 int run_command_list(const char *cmd, int len, int flag);
-void	init_cmd_timeout(void);
-void	reset_cmd_timeout(void);
 extern char console_buffer[];
 
 /* arch/$(ARCH)/lib/board.c */