[MLIR][Interfaces] Change MemorySlotInterface to use OpBuilder (#91341)

This commit changes the `MemorySlotInterface` back to using `OpBuilder`
instead of a rewriter. This was originally introduced in
https://reviews.llvm.org/D150432 but it was shown that patterns are a
bad idea for both Mem2Reg and SROA.
Mem2Reg suffers from the usage of a rewriter due to being forced to
create new basic blocks. This is an issue, as it leads to the
invalidation of the dominance information, which can be expensive to
recompute.