* src/vm/jit/allocator/simplereg.c: Ensured proper alignment of all

* src/vm/jit/allocator/simplereg.c: Ensured proper alignment of all
doubles and longs if ALIGN_[DOUBLES|LONGS]_IN_MEMORY is defined.
(local_regalloc): Fixed error for HAS_ADREDD_REGISTER_FILE - else was
missing.  Ensured use of unused argument register in leafmethod before
use of saved registers.  Regarded PACK_REGS for
SUPPORT_COMBINE_INTEGER_REGISTER archs for unused integer argument
registers.
* src/vm/jit/i386/arch.h: Added defines for
ALIGN_[DOUBLES|LONGS]_IN_MEMORY.
* src/vm/jit/powerpc/arch.h: Likewise.