pgsql: Replace most StaticAssertStmt() with StaticAssertDecl()

Replace most StaticAssertStmt() with StaticAssertDecl()

Similar to commit 75f49221c22, it is preferable to use
StaticAssertDecl() instead of StaticAssertStmt() when possible.

Discussion:
https://www.postgresql.org/message-id/flat/CA%2BhUKGKvr0x_oGmQTUkx%3DODgSksT2EtgCA6LmGx_jQFG%3DsDUpg%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/493eb0da31be4520252e1af723342dc7ead0c3e5

Modified Files
--------------
contrib/hstore/hstore_compat.c         |  9 ++++-----
src/backend/access/heap/vacuumlazy.c   |  5 +++--
src/backend/access/table/tableam.c     |  6 +++---
src/backend/access/transam/parallel.c  |  7 ++++---
src/backend/storage/buffer/bufmgr.c    |  4 ++--
src/backend/storage/file/fd.c          | 17 -----------------
src/backend/storage/ipc/waiteventset.c |  3 ++-
src/backend/utils/adt/mac.c            |  2 +-
src/backend/utils/cache/inval.c        |  2 +-
src/include/storage/fd.h               | 16 ++++++++++++++++
10 files changed, 36 insertions(+), 35 deletions(-)