Add cli_ prefix to readline functions

This makes it clear where the code resides.

Signed-off-by: Simon Glass <sjg@chromium.org>

common/cmd_i2c.c

@@ -613,7 +613,7 @@ mod_i2c_mem(cmd_tbl_t *cmdtp, int incrflag, int flag, int argc, char * const arg
 				printf(" %08lx", data);
 		}
 
-		nbytes = readline (" ? ");
+		nbytes = cli_readline(" ? ");
 		if (nbytes == 0) {
 			/*
 			 * <CR> pressed as only input, don't modify current