config.mk: Remove obsolete variables verification

ARM_TOOLCHAIN_DIR and ARM_GCC_PREFIX are obsolete.
Their references have been removed by 5e98be7 ("Cleanup Makefile").

Remove remained verification.

Signed-off-by: Aleksandr Bulyshchenko <[email protected]>
Acked-by: Jerome Forissier <[email protected]>
Acked-by: Jens Wiklander <[email protected]>

Author: AleksandrBulyshchenko

Diff for: config.mk

@@ -66,9 +66,3 @@ OO := $(if $(filter /%,$(O)),$(O),$(CURDIR)/../$(O))
 
 # Check that settings are coherent.
 
-ifdef ARM_TOOLCHAIN_DIR
-ifeq ($(wildcard ${ARM_TOOLCHAIN_DIR}/bin/${ARM_GCC_PREFIX}-gcc),)
-  $(error "ARM_TOOLCHAIN_DIR wrongly setup. Is ${ARM_TOOLCHAIN_DIR}")
-endif
-endif
-