Inconsistent subassembly object ID for different sizes of size_t

[clonker]

Description

When compiling solc for different sizes of size_t, e.g., comparing emscripten and linux builds, the object ID of subassembly paths as determined here

https://github.com/ethereum/solidity/blob/a65229279d769a7b2936aef2aa802d77abbdc343/libevmasm/Assembly.cpp#L1825

will be inconsistent between the two builds. This potentially leads to inconsistent assembly text between emscripten and native 64 bit builds.

We should test the precise impact this has and fix it to the 64 bit behavior.