pgsql: Rename removable xid function for consistency.

Rename removable xid function for consistency.

GlobalVisIsRemovableFullXid() is now GlobalVisCheckRemovableFullXid().
This is consistent with the general convention for FullTransactionId
equivalents of functions that deal with TransactionId values.  It now
matches the nearby GlobalVisCheckRemovableXid() function, which performs
the same check for callers that use TransactionId values.

Oversight in commit dc7420c2c92.

Discussion: https://postgr.es/m/CAH2-Wzmes12jFNDcVgpU89Vp=r6uLFrE-MT0fjSWGsE70UiNaA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/617fffee8a6f350ff03069e2843ecd039ea06ccc

Modified Files
--------------
src/backend/access/gist/gistutil.c  | 2 +-
src/backend/access/gist/gistxlog.c  | 2 +-
src/backend/storage/ipc/procarray.c | 2 +-
src/include/utils/snapmgr.h         | 2 +-
4 files changed, 4 insertions(+), 4 deletions(-)