[BUGFIX] Remove "[newlog()] " from DataHandler log info

DataHandlers' newlog() function is a shorthand method that
should act as a simple API, which it does, but it also adds
a "[newlog()] " info in front of the error message, which is
completely useless and only clutters DB and the log module.

Resolves: #83012
Releases: master, 8.7
Change-Id: I9e1ea083461de9cdf66fad1a30019e51130a0186
Reviewed-on: https://review.typo3.org/54660


Reviewed-by: Andreas Fernandez <typo3@scripting-base.de>
Tested-by: Andreas Fernandez <typo3@scripting-base.de>
Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Frans Saris <franssaris@gmail.com>
Reviewed-by: Markus Klein <markus.klein@typo3.org>
Tested-by: Markus Klein <markus.klein@typo3.org>