pgsql: Make error message of pageinspect more consistent for raw pagei

Make error message of pageinspect more consistent for raw page inputs

There is a copy-paste error from bt_page_items() which got into
bt_page_items_bytea().  A second message in get_raw_page_internal() was
inconsistent with all the other sub-modules.

Author: Ashutosh Sharma
Discussion: https://postgr.es/m/CAE9k0PnZuZ3PVXSyQY91-53E8JKFcaSyknFqqU43r9MabKSYZA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/59eb12c9c5a5aa980ed89363d143edad712d2c1d

Modified Files
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contrib/pageinspect/btreefuncs.c | 2 +-
contrib/pageinspect/rawpage.c    | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)