pgsql: Use C11 alignas instead of pg_attribute_aligned

Use C11 alignas instead of pg_attribute_aligned

Replace pg_attribute_aligned with C11 alignas, for consistency with
current conventions.

(These new uses were added by commit fbc57f2bc2e, which was developed
concurrently with the switch from pg_attribute_aligned to C11 standard
alignas, and it ended up being committed with the "old" style.)

Reviewed-by: John Naylor <johncnaylorls@gmail.com>
Discussion: /messages/by-id/CANWCAZaKhE+RD5KKouUFoxx1EbUNrNhcduM1VQ=DkSDadNEFng@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8061bfd15abe4d6943ac1563617c19fc069aad70

Modified Files
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src/port/pg_crc32c_armv8.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)