mx7: Remove BMODE support

i.MX7 does not support BMODE due to the erratum e10574 ("Watchdog:
A watchdog timeout or software trigger will not reset the SOC"), so
remove its support.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig
index 3aec89d..a1566cc 100644
--- a/arch/arm/mach-imx/Kconfig
+++ b/arch/arm/mach-imx/Kconfig
@@ -46,7 +46,7 @@
 config CMD_BMODE
 	bool "Support the 'bmode' command"
 	default y
-	depends on ARCH_MX7 || ARCH_MX6 || ARCH_MX5
+	depends on ARCH_MX6 || ARCH_MX5
 	help
 	  This enables the 'bmode' (bootmode) command for forcing
 	  a boot from specific media.