Enable VIA Padlock on x86_64 platforms

• cipher/rijndael.c: Duplicate x86 assembly and convert to x86_64.
• random/rndhw.c: Likewise.
• src/hwfeatures.c: Likewise. --

Changes made to the x86 assembly:

• *l -> *q (long -> quad)
• e registers -> r registers (use widest registers available)
• don't mess with ebx GOT register

Tested with make check on VIA Nano X2 L4350

• Signed-off-by: Rafaël Carré <funman@videolan.org>