pgsql: Remove unneeded casts of BufferGetPage() result

Remove unneeded casts of BufferGetPage() result

BufferGetPage() already returns type Page, so casting it to Page
doesn't achieve anything. A sizable number of call sites does this
casting; remove that.

This was already done inconsistently in the code in the first import
in 1996 (but didn't exist in the pre-1995 code), and it was then
apparently just copied around.

Author: Kirill Reshke <reshkekirill(at)gmail(dot)com>
Reviewed-by: Chao Li <li(dot)evan(dot)chao(at)gmail(dot)com>
Reviewed-by: Richard Guo <guofenglinux(at)gmail(dot)com>
Reviewed-by: Álvaro Herrera <alvherre(at)kurilemu(dot)de>
Reviewed-by: Peter Eisentraut <peter(at)eisentraut(dot)org>
Discussion: https://www.postgresql.org/message-id/flat/CALdSSPgFhc5=vLqHdk-zCcnztC0zEY3EU_Q6a9vPEaw7FkE9Vw(at)mail(dot)gmail(dot)com

Branch
------
master

Details
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https://git.postgresql.org/pg/commitdiff/710e6c4301ee3c739a171ea12ed141b1f8df0d93

Modified Files
--------------
contrib/amcheck/verify_gin.c | 4 ++--
contrib/bloom/blvacuum.c | 2 +-
contrib/pgstattuple/pgstatindex.c | 2 +-
contrib/pgstattuple/pgstattuple.c | 4 ++--
src/backend/access/brin/brin_xlog.c | 12 ++++++------
src/backend/access/gin/ginvacuum.c | 2 +-
src/backend/access/gin/ginxlog.c | 4 ++--
src/backend/access/gist/gist.c | 14 +++++++-------
src/backend/access/gist/gistbuild.c | 4 ++--
src/backend/access/gist/gistvacuum.c | 4 ++--
src/backend/access/gist/gistxlog.c | 10 +++++-----
src/backend/access/hash/hash_xlog.c | 18 +++++++++---------
src/backend/access/heap/heapam.c | 2 +-
src/backend/access/heap/heapam_handler.c | 2 +-
src/backend/access/heap/heapam_xlog.c | 8 ++++----
src/backend/access/heap/pruneheap.c | 2 +-
src/backend/access/heap/visibilitymap.c | 2 +-
src/backend/access/nbtree/nbtxlog.c | 28 ++++++++++++++--------------
src/backend/access/spgist/spgvacuum.c | 4 ++--
src/backend/access/spgist/spgxlog.c | 6 +++---
src/backend/access/transam/xlogutils.c | 2 +-
src/backend/commands/sequence.c | 2 +-
22 files changed, 69 insertions(+), 69 deletions(-)