x86: make fixups wordsize agnostic

This patch uses the _ASM_ALIGN and _ASM_PTR macros
to make the fixups in native_read/write_msr_safe look the same
for x86_64 and i386. Besides using this macros, we also have to
take the explicit instruction suffixes out. It's okay
because all this instructions uses registers, and can be sized by
them.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>