pgsql: Further code review of port/simd.h

Further code review of port/simd.h

Add missing declaration per existing style, and fix a couple typos.

Nathan Bossart and Julien Rouhaud

Discussion: https://www.postgresql.org/message-id/20220829171712.GA509233%40nathanxps13
Discussion: https://www.postgresql.org/message-id/20220830022636.qrcbcecmhztbxrwa%40jrouhaud

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/865424627db638acdbe4b5d0384d0b9cd34838a5

Modified Files
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src/include/port/simd.h | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)