[lldb] Add an overload to SetModuleLoadAddress that takes an unsigned value

Currently, SBTarget::SetModuleLoadAddress does not accept large slides
needed to load images in high memory. This function should always have
taken an unsigned as the slide, as it immediately passes it to
Target::SetSectionLoadAddress which takes an unsigned.

This patch adds an overload and exposes that to SWIG instead of the
signed variant. I've marked the signed variant as deprecated and added
check that the slide is positive.

rdar://101355155

Differential revision: https://reviews.llvm.org/D147482