casts test: use const-ref parameters
casts test: use const-ref parameters

simdarrays really better be passed as const-ref (in general). This also
gets rid of the overalignment warnings from GCC

Signed-off-by: Matthias Kretz <372ea4eca737a13cd010ee806d4ce7b98ee71550@kde.org>

chr-engwer/Vc,VcDevel/Vc,VcDevel/Vc,VcDevel/Vc,chr-engwer/Vc,chr-engwer/Vc,VcDevel/Vc