.stack_sizes section output is incorrect

When using the clang option `-fstack-size-section`, the section `.stack_sizes` is added in the object file.
The contents of this section are a list of tuples, composed of an IRAM offset (pointer size, 4 bytes for us) and a size (encoded as an unsigned LEB128).

In the case of a DPU program, the offsets seem OK, but the sizes are 0 for the leaf functions.