hikey960: Avoid failures if sdcardfs.ko isn't present

sdcardfs isn't being built in android12-5.4 anymore, so
we need to remove it from the modules list for the initrd,
but existing prebuilt kernels still provide it, so
conditionalize it so we don't get errors with newer built
kernels.

Signed-off-by: John Stultz <john.stultz@linaro.org>
Change-Id: I0f0f810960211034055dfabb75ef92d0167fb0f0
diff --git a/hikey960.mk b/hikey960.mk
index 0107fad..3a979f8 100644
--- a/hikey960.mk
+++ b/hikey960.mk
@@ -47,10 +47,11 @@
 ifneq ($(HIKEY_USES_GKI),)
   HIKEY_MOD_DIR := device/linaro/hikey-kernel/hikey960/$(TARGET_KERNEL_USE)
   HIKEY_MODS := $(wildcard $(HIKEY_MOD_DIR)/*.ko)
+  SDCARDFS_KO := $(wildcard $(HIKEY_MOD_DIR)/sdcardfs*.ko)
   ifneq ($(HIKEY_MODS),)
     BOARD_VENDOR_KERNEL_MODULES += $(HIKEY_MODS)
     BOARD_VENDOR_RAMDISK_KERNEL_MODULES += \
 	$(HIKEY_MOD_DIR)/ion_cma_heap.ko \
-	$(HIKEY_MOD_DIR)/sdcardfs.ko
+	$(SDCARDFS_KO)
   endif
 endif