MIPS: Followup 'Fix Add HArrayBufferNotNeutered instruction'.
MIPS: Followup 'Fix Add HArrayBufferNotNeutered instruction'.

Followup fix of nit discussed in Issue 1111003002.

BUG=

Review URL: https://codereview.chromium.org/1112793004

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#28130}

UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh