Fix descriptor output in ECPG.

While working on most platforms the old way sometimes created alignment
problems. This should fix it. Also the regresion tests were updated to test for
the reported case.

Report and fix by MauMau <maumau307@gmail.com>

Conflicts:
	src/interfaces/ecpg/preproc/type.c
	src/interfaces/ecpg/test/expected/sql-desc.c