imx8mq_evk/README: fix DDR training firmware path

Remove a redundant directory level.

Reported-by: Ofer Heifetz <ofer.heifetz@valens.com>
Tested-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
diff --git a/board/freescale/imx8mq_evk/README b/board/freescale/imx8mq_evk/README
index 004fa3f..2529f7d 100644
--- a/board/freescale/imx8mq_evk/README
+++ b/board/freescale/imx8mq_evk/README
@@ -20,7 +20,7 @@
 $ chmod +x firmware-imx-7.9.bin
 $ ./firmware-imx-7.9.bin
 $ cp firmware-imx-7.9/firmware/hdmi/cadence/signed_hdmi_imx8m.bin $(srctree)
-$ cp firmware-imx-7.9/firmware-imx-7.9/firmware/ddr/synopsys/lpddr4*.bin $(srctee)
+$ cp firmware-imx-7.9/firmware/ddr/synopsys/lpddr4*.bin $(srctee)
 
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