normalize_pot(): split long line somewhat (refs: #12641).

refresh-translations

@@ -29,7 +29,9 @@ LOCALE_BASEDIR=config/chroot_local-includes/usr/share/locale
 ### Functions
 
 normalize_pot () {
-    sed --regexp-extended -i 's@^"Content-Type: text/plain; charset=CHARSET\\n"@"Content-Type: text/plain; charset=UTF-8\\n"@' "${@}"
+    sed --regexp-extended \
+        -i 's@^"Content-Type: text/plain; charset=CHARSET\\n"@"Content-Type: text/plain; charset=UTF-8\\n"@' \
+        "${@}"
 }
 
 prog_potfile () {