Allow phpdoc blocks before define/defined

Right now we are presenting any phpdoc block before define/defined as error:

/**

36: Inline doc block comments are not allowed; use "/* Comment */" or "// Comment" instead

And our coding style says that they must be commented using phpdoc:

http://docs.moodle.org/dev/Coding_style#Defines

So this is about to stop reporting them as errors, but without killing the sniff for other functions.

Ciao