pgsql: Move new LOCKTAG_DATABASE_FROZEN_IDS to end of enum LockTagType.

Move new LOCKTAG_DATABASE_FROZEN_IDS to end of enum LockTagType.

Several PGXN modules reference LockTagType values; renumbering would
force a recompile of those modules.  Oversight in back-patch of today's
commit 566372b3d6435639e4cc4476d79b8505a0297c87.  Back-patch to released
branches, v12 through 9.5.

Reported by Tom Lane.

Discussion: https://postgr.es/m/921383.1597523945@sss.pgh.pa.us

Branch
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REL9_5_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/d8a22a387b484e73e5a938874dc3a737452c4f1a

Modified Files
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src/backend/utils/adt/lockfuncs.c | 4 ++--
src/include/storage/lock.h        | 8 ++++----
2 files changed, 6 insertions(+), 6 deletions(-)