pgsql: Make initdb's selection of default text search configuration

Log Message:
-----------
Make initdb's selection of default text search configuration depend
only on the 'language' part of the locale name, ignoring the country code.
We may need to be smarter later when there are more built-in configurations,
but for now this is good enough and avoids having to bloat the table.

Modified Files:
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    pgsql/src/bin/initdb:
        initdb.c (r1.148 -> r1.149)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/initdb/initdb.c?r1=1.148&r2=1.149)