[BUGFIX] PHP7 always_populate_raw_post_data is removed.

Since PHP7 always_populate_raw_post_data in php.ini is removed. This
means that the absense of this setting is like setting it to -1 for
PHP 5.6 installations. We give a OkStatus in InstallTool for PHP7.

Resolves: #69378
Releases: master
Change-Id: Iab2ca2077c508dbeec90b97bfd41dd7c992ebb74
Reviewed-on: http://review.typo3.org/42977


Reviewed-by: Michael Oehlhof <typo3@oehlhof.de>
Tested-by: Michael Oehlhof <typo3@oehlhof.de>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>