pgsql: Avoid including clog.h in proc.h

Avoid including clog.h in proc.h

The number of .c files that must include access/clog.h can currently be
counted on one's fingers and miss only one (assuming one has the usual
number of hands).  However, due to indirect inclusion via proc.h,
there's a lot of files that are pointlessly including it.  This is easy
to avoid with the easy trick implemented by this commit.

Author: Álvaro Herrera <alvherre@kurilemu.de>
Discussion: https://postgr.es/m/202603221856.iwlhitt6dxxx@alvherre.pgsql

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/f227b7b20c36b7348867eec48d539d28cfdf831c

Modified Files
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src/backend/storage/lmgr/proc.c | 1 +
src/include/storage/proc.h      | 4 +++-
2 files changed, 4 insertions(+), 1 deletion(-)