Add project specific definitions.mk files

Just like we do with build/tasks/*.mk, we also look for project
specific definitions.mk files.

Test: TreeHugger
Bug: 243024627
Change-Id: I7f07546582eb02bba245a1f927a11efc1ddc3c6f
diff --git a/core/definitions.mk b/core/definitions.mk
index d3eab95..cd36011 100644
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -3836,6 +3836,10 @@
 -include $(TOPDIR)vendor/*/build/core/definitions.mk
 -include $(TOPDIR)device/*/build/core/definitions.mk
 -include $(TOPDIR)product/*/build/core/definitions.mk
+# Also the project-specific definitions.mk file
+-include $(TOPDIR)vendor/*/*/build/core/definitions.mk
+-include $(TOPDIR)device/*/*/build/core/definitions.mk
+-include $(TOPDIR)product/*/*/build/core/definitions.mk
 
 # broken:
 #	$(foreach file,$^,$(if $(findstring,.a,$(suffix $file)),-l$(file),$(file)))