Fix crash on SPARC due to improper alignment of allocated memory

I believe that you should be able to drop 'defined(__sun)' completely
from this clause, as Solaris on x86 hardware probably does not have
strict alignment requirements, but I don't have a way to test that.

Thanks to Jurij Smakov <jurij@wooyd.org>.

Signed-off-by: Chris Lamb <lamby@debian.org>