[llvm] [Support] Add decodeULEB128AndInc/decodeSLEB128AndInc (PR #85739)

[David Blaikie via llvm-commits]

dwblaikie wrote:

@MaskRay I think the basic request/requirement here should be that these new APIs be no worse at error handling than the ones they're wrapping: Please add the extra optional error reporting parameters.

Ideally, imo, we should be making error handling more explicit/non-optional than these APIs are. Ideally new APIs (including these wrappers) would include non-optional error handling (Error/Expected returning) 

https://github.com/llvm/llvm-project/pull/85739