pgsql: Rename heapam_index_fetch_tuple argument for clarity.

Rename heapam_index_fetch_tuple argument for clarity.

Rename heapam_index_fetch_tuple's call_again argument to heap_continue,
for consistency with the pointed-to variable name (IndexScanDescData's
xs_heap_continue field).

Preparation for an upcoming commit that will move index scan related
heapam functions into their own file.

Author: Peter Geoghegan <pg(at)bowt(dot)ie>
Reviewed-By: Andres Freund <andres(at)anarazel(dot)de>
Discussion: https://postgr.es/m/bmbrkiyjxoal6o5xadzv5bveoynrt3x37wqch7w3jnwumkq2yo@b4zmtnrfs4mh

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/1adff1a0c558ecaef4fbe4cf343c426a59414749

Modified Files
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src/backend/access/heap/heapam_handler.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)