pgsql: Simplify dxsyn_lexize().

Simplify dxsyn_lexize().

There's no need to create and free a temporary copy of the input,
since str_tolower() is already able to cope with not-certainly-
nul-terminated input. (Before v18, copying was needed because
this code used lowerstr(), but now we can do without.)

Author: Ayush Tiwari <ayushtiwari(dot)slg01(at)gmail(dot)com>
Reviewed-by: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Discussion: https://postgr.es/m/19525-b0be8e4eb7dbaf07@postgresql.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/9f03dab4574bd2820eec6902c2ef12b28c706733

Modified Files
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contrib/dict_xsyn/dict_xsyn.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)