Escape the value of the field CType in tt_content.default.

Resolves: #73450
Releases: master, 7.6, 6.2
Security-Commit: fa4c55b136648dd01115c346d9fd0c90b303f2d1
Security-Bulletins: TYPO3-CORE-SA-2016-005, 006, 007, 008
Change-Id: Ica19c572bf46b6f2b11333b6759804d3537e7469
Reviewed-on: https://review.typo3.org/46829


Reviewed-by: Oliver Hader <oliver.hader@typo3.org>
Tested-by: Oliver Hader <oliver.hader@typo3.org>