[RISC-V] Bad immediate value for Zcmp instructions with E extension (#84925)

When we are using the Zcmp extension together with the E extension in
32-bit mode and we need to spill both callee-saved registers as well as
needing a couple of 32-bit stack slots, we emit a meaningless stack
adjustment with cm.push/cm.popret. Furthermore this leads to the stack
slot for the ra being clobbered so control returns to a random location.

This is just a pre-commit test so that the PR for the fix shows the
difference in code generation.