pgsql: Remove preprocessor guards from injection points

Remove preprocessor guards from injection points

When defining an injection point there is no need to wrap the definition
with USE_INJECTION_POINT guards, the INJECTION_POINT macro is available
in all builds. Remove to make the code consistent.

Author: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: /messages/by-id/OSCPR01MB14966C8015DEB05ABEF2CE077F51FA@OSCPR01MB14966.jpnprd01.prod.outlook.com
Backpatch-through: 17

Branch
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REL_17_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/53a2246ddf9b1e641654dd0654ff8f24e952920a

Modified Files
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src/backend/access/transam/xlog.c | 2 --
1 file changed, 2 deletions(-)