cmake: fix bug introduced with `PRODUCT_BUILD_DIR` implementation
The recent change to use DIRECT_BUILD
introduced an issue where
the BUILD_PATH
is not being updated as intended. This fix ensures
PRODUCT_BUILD_DIR
is correctly set and used throughout the
Makefile wrapper.
Signed-off-by: Leandro Belli leandro.belli@arm.com Change-Id: I4551fda576b9dedad33dd4be540dce687aa5bba1