imx8qxp_mek: Remove unused function detail_board_ddr_info()

detail_board_ddr_info() is not used anywhere, so simply remove it.

This function is only used by Layerscape, not by i.MX.

This was detected by the following sparse warning:

board/freescale/imx8qxp_mek/imx8qxp_mek.c:115:6: warning: no previous
prototype for ‘detail_board_ddr_info’ [-Wmissing-prototypes]

Signed-off-by: Alifer Moraes <alifer.wsdm@gmail.com>

board/freescale/imx8qxp_mek/imx8qxp_mek.c

@@ -113,11 +113,6 @@ int board_init(void)
 	return 0;
 }
 
-void detail_board_ddr_info(void)
-{
-	puts("\nDDR    ");
-}
-
 /*
  * Board specific reset that is system reset.
  */