Make Qt 4.8 also compile with the LSB SDK on Linux

Generate worse code.

This is similar to Qt5 commits 46bfd84fdc24fa3e3e721a5dda6cfbebe75be073
and c69106d1bf66d64e046c4f639542457151187dfc.

Task-number: QTBUG-25336
Change-Id: Idd61c23d2b528db9d8c7895df008b9c1b0e2a2a4
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>