pgsql: Convert macros to static inline functions (block.h)

Convert macros to static inline functions (block.h)

Remove BlockIdIsValid(), which wasn't used and is unnecessary.

Remove BlockIdCopy(), which wasn't used and can be done by struct
assignment.

(BlockIdEquals() also isn't used, but seems reasonable to keep
around.)

Reviewed-by: Amul Sul <sulamul@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/5b558da8-99fb-0a99-83dd-f72f05388517%40enterprisedb.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d63d957e330c611f7a8c0ed02e4407f40f975026

Modified Files
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src/include/storage/block.h | 53 ++++++++++++++++++++-------------------------
1 file changed, 23 insertions(+), 30 deletions(-)