[kcms/recentFiles] Fix translation catalog name

We use kcm_recentFiles in one place and kcm_recentFiles5 in another, breaking translations

(cherry picked from commit abe324ca)

kcms/recentFiles/Messages.sh

 #! /usr/bin/env bash
 $EXTRACTRC `find . -name \*.rc -o -name \*.ui -o -name \*.kcfg` >> rc.cpp
-$XGETTEXT `find . -name \*.qml -o -name \*.h -o -name \*.js -o -name \*.cpp` -o $podir/kcm_recentFiles5.pot
+$XGETTEXT `find . -name \*.qml -o -name \*.h -o -name \*.js -o -name \*.cpp` -o $podir/kcm_recentFiles.pot
 rm -f rc.cpp