Drop support for target files with no recovery.fstab.

Change-Id: I099298cfffc2546975732a3bf0df60f96ccbdac4
Meanwhile don't build the ota and update zip files if no recovery.fstab
found.
diff --git a/core/Makefile b/core/Makefile
index d5fd9a8..1a5d294 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -1025,6 +1025,7 @@
 ifneq ($(TARGET_PRODUCT),sdk)
 ifneq ($(TARGET_DEVICE),generic)
 ifneq ($(TARGET_NO_KERNEL),true)
+ifneq ($(recovery_fstab),)
 
 # -----------------------------------------------------------------
 # OTA update package
@@ -1077,6 +1078,7 @@
 .PHONY: updatepackage
 updatepackage: $(INTERNAL_UPDATE_PACKAGE_TARGET)
 
+endif    # recovery_fstab is defined
 endif    # TARGET_NO_KERNEL != true
 endif    # TARGET_DEVICE != generic
 endif    # TARGET_PRODUCT != sdk