common: Move get_ticks() function out of common.h

This function belongs in time.h so move it over and add a comment.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>

common/cli_readline.c

@@ -11,6 +11,7 @@
 #include <common.h>
 #include <bootretry.h>
 #include <cli.h>
+#include <time.h>
 #include <watchdog.h>
 
 DECLARE_GLOBAL_DATA_PTR;