armv8: fsl : create bootcmd and mcinitcmd as per boot source

NXP platforms expect custom bootcmd and mcinitcmd to be
updated as per boot source with default environment.
Check env variable fsl_bootcmd_mcinitcmd_set to prepare
bootcmd and mcinitcmd

Fixes: cbf77d201870 (armv8: fsl-layerscape: Fix automatic
setting of bootmcd with TF-A)

Signed-off-by: Wasim Khan <wasim.khan@nxp.com>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>
diff --git a/arch/arm/cpu/armv8/fsl-layerscape/soc.c b/arch/arm/cpu/armv8/fsl-layerscape/soc.c
index 1641b65..42a0968 100644
--- a/arch/arm/cpu/armv8/fsl-layerscape/soc.c
+++ b/arch/arm/cpu/armv8/fsl-layerscape/soc.c
@@ -953,12 +953,15 @@
 #endif
 #ifdef CONFIG_TFABOOT
 	/*
-	 * Set bootcmd and mcinitcmd if they don't exist in the environment.
+	 * Set bootcmd and mcinitcmd if "fsl_bootcmd_mcinitcmd_set" does
+	 * not exists in env
 	 */
-	if (!env_get("bootcmd"))
+	if (env_get_yesno("fsl_bootcmd_mcinitcmd_set") <= 0) {
+		// Set bootcmd and mcinitcmd as per boot source
 		fsl_setenv_bootcmd();
-	if (!env_get("mcinitcmd"))
 		fsl_setenv_mcinitcmd();
+		env_set("fsl_bootcmd_mcinitcmd_set", "y");
+	}
 #endif
 #ifdef CONFIG_QSPI_AHB_INIT
 	qspi_ahb_init();