Handle moves of non-16 size to/from CCR

[knickish]

Was attempting to debug #107939 and kept hitting the Need DR8 register to copy CCR. According to the datasheet, the move to/from the dest/src register is always word sized, and only the low-order bytes will be copied (without sext/zext). PR is incomplete for now, and builds on #107591 anyway so needs to wait for a review/merge on that

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[github-actions]

✅ With the latest revision this PR passed the C/C++ code formatter.