cmd_df.c: Delete this clearly unused source file.

Nothing appears to use or compile cmd_df.c anymore.

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>

common/cmd_df.c

@@ -1,36 +0,0 @@
-/*
- * Command for accessing DataFlash.
- *
- * Copyright (C) 2008 Atmel Corporation
- */
-#include <common.h>
-#include <df.h>
-
-static int do_df(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
-{
-	const char *cmd;
-
-	/* need at least two arguments */
-	if (argc < 2)
-		goto usage;
-
-	cmd = argv[1];
-
-	if (strcmp(cmd, "init") == 0) {
-		df_init(0, 0, 1000000);
-		return 0;
-	}
-
-	if (strcmp(cmd, "info") == 0) {
-		df_show_info();
-		return 0;
-	}
-
-usage:
-	return CMD_RET_USAGE;
-}
-
-U_BOOT_CMD(
-	sf,	2,	1,	do_serial_flash,
-	"Serial flash sub-system",
-	"probe [bus:]cs		- init flash device on given SPI bus and CS")