linux kernel with defconfig always use kernel modules

mk/kernel-build.mk

@@ -12,6 +12,10 @@ endif
 ifeq ($(ADK_TARGET_LINUX_KERNEL_USE_CUSTOMCONFIG),y)
 KERNEL_MODULES_USED:=$(shell grep -s =m $(ADK_TOPDIR)/$(ADK_TARGET_LINUX_KERNEL_CUSTOMCONFIG_PATH))
 endif
+# assume kernel modules when defconfig is in use
+ifeq ($(ADK_TARGET_LINUX_KERNEL_USE_DEFCONFIG),y)
+KERNEL_MODULES_USED:=y
+endif
 
 KERNEL_FILE:=$(ADK_TARGET_KERNEL)
 KERNEL_TARGET:=$(ADK_TARGET_KERNEL)