pgsql: Issue 'mkdir' hint when replying CREATE TABLESPACE in recovery

Log Message:
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Issue 'mkdir' hint when replying CREATE TABLESPACE in recovery mode.

Per idea from Fujii Masao

Modified Files:
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pgsql/src/backend/commands:
tablespace.c (r1.74 -> r1.75)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/tablespace.c?r1=1.74&r2=1.75)