pgsql: Remove no longer needed casts from Pointer

Remove no longer needed casts from Pointer

These casts used to be required when Pointer was char *, but now it's
void * (commit 1b2bb5077e9), so they are not needed anymore.

Author: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Discussion: /messages/by-id/4154950a-47ae-4223-bd01-1235cc50e933@eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e158fd4d68f44d0872c1d2053067fe306cc9d2b2

Modified Files
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contrib/amcheck/verify_gin.c | 2 +-
contrib/pg_trgm/trgm_gin.c | 6 ++----
src/backend/access/gin/ginentrypage.c | 2 +-
src/backend/utils/adt/jsonb_gin.c | 12 ++++--------
4 files changed, 8 insertions(+), 14 deletions(-)