pgsql: Fix comments in heaptuple.c

Fix comments in heaptuple.c

Since e27f4ee0a701, fastgetattr() and heap_getattr() are not macros, but
inlined functions.

Author: Junwang Zhao
Reviewed-by: Stepan Neretin
Discussion: https://postgr.es/m/CAEG8a3JS-JKWWyOcM7BU=vPqFXa3W7mZSHnvc3CBqx=tC+3SCA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/526b54ece3f6b0bc474c0498d94780a38a6648a2

Modified Files
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src/backend/access/common/heaptuple.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)