pgsql: Use fabsf() instead of Abs() or fabs() where appropriate

Use fabsf() instead of Abs() or fabs() where appropriate

This function is new in C99.

Reviewed-by: Zhang Mingli <zmlpostgres@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/4beb42b5-216b-bce8-d452-d924d5794c63%40enterprisedb.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e4c61bedcb791fe79fdc4e96a3a7ab59b0dbacaf

Modified Files
--------------
contrib/btree_gist/btree_float4.c | 2 +-
contrib/intarray/_int_gist.c      | 2 +-
contrib/seg/seg.c                 | 5 +++--
src/backend/utils/adt/float.c     | 2 +-
4 files changed, 6 insertions(+), 5 deletions(-)