[platform][imx] Remove dependency on openssl

It is not used anymore.

Change-Id: I7fa911f3d4be9289dc7b61b7471d9442ffe58050
diff --git a/platform/imx/rules.mk b/platform/imx/rules.mk
index 7f495dd..280ff5e 100644
--- a/platform/imx/rules.mk
+++ b/platform/imx/rules.mk
@@ -73,7 +73,6 @@
 MODULE_DEPS += \
 	dev/interrupt/arm_gic \
 	dev/timer/arm_generic \
-	openssl
 
 GLOBAL_DEFINES += \
 	CONFIG_CONSOLE_TTY_BASE=$(CONFIG_CONSOLE_TTY_BASE) \