trusty: fix kernel build warning with soc/gs dependency

We get warning that "private/google-modules/soc/gs/Module.symvers" is
missing, but this symbol should not be necessary after we removed the
cyclic dependency.

Bug: 309892219
Change-Id: I01cb2c61db387af505e65861a3238a6c13f58e30
Signed-off-by: Ji Soo Shin <jisshin@google.com>
diff --git a/Makefile b/Makefile
index 8e4db7f..65946e6 100644
--- a/Makefile
+++ b/Makefile
@@ -4,8 +4,6 @@
 
 EXTRA_CFLAGS += -Werror
 
-include $(KERNEL_SRC)/../private/google-modules/soc/gs/Makefile.include
-
 modules modules_install clean:
 	$(MAKE) -C $(KERNEL_SRC) M=$(M) W=1 \
 	EXTRA_CFLAGS="$(EXTRA_CFLAGS)" KBUILD_EXTRA_SYMBOLS="$(EXTRA_SYMBOLS)" $(@)