Generate stack usage information only when enabled

This will only generate the .su files when CONFIG_STACK_USAGE
is specified, otherwise the tree will be full of .su files.

Change-Id: I3ffc7a7f5ab09aaae49ff65e8ad5de0832370777
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2 files changed