Fixes
qtbase\qmake\generators\makefiledeps.cpp(985): warning C4267: '+=': conversion from 'size_t' to 'int', possible loss of data
qtbase\qmake\generators\makefiledeps.cpp(986): warning C4267: '+=': conversion from 'size_t' to 'int', possible loss of data
Pick-to: 6.2
Change-Id: I7c6b4f36dc383db420c10d674666d58dbf29d2dd
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>