[BUGFIX] Avoid PHP 8 warnings when processing the INTinclude-scripts

Avoid PHP warnings when calling the method to process INTinclude
scripts when jsInline or jsFooterInline was set.

Previously, the jsInline and jsFooterInline was called after
$TSFE->INTincScript_loadJScode(), where TSFE considered
there were no *_INT objects, however, they were processed
later-on, thus no "divKey" was set and a PHP warning
was set.

Change-Id: Ie639d58a2efce10177a41042080534ce26a1a291
Resolves: #100216
Releases: main, 11.5
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/78065


Tested-by: Nikita Hovratov <nikita.h@live.de>
Tested-by: Albrecht Köhnlein <ak@koehnlein.eu>
Tested-by: core-ci <typo3@b13.com>
Reviewed-by: Albrecht Köhnlein <ak@koehnlein.eu>
Reviewed-by: Nikita Hovratov <nikita.h@live.de>