pgsql: plperl: Fix breakage of c89f409749c in back branches.

plperl: Fix breakage of c89f409749c in back branches.

ppport.h was only updated in 05798c9f7f0 (master). Unfortunately my commit
c89f409749c uses PERL_VERSION_LT which came in with that update. Breaking most
buildfarm animals.

I should have noticed that...

We might want to backpatch the ppport update instead, but for now lets get the
buildfarm green again.

Discussion: https://postgr.es/m/20220131015130.shn6wr2fzuymerf6@alap3.anarazel.de
Backpatch: 10-14, master doesn't need it

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/d81cac47a829c3e2c729ef98acaf132adb7ff3ae

Modified Files
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src/pl/plperl/plperl.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)