Labels should end by colon (':'), nasm requires it.
Provide nasm compatibility. No binary change by this patch with yasm
on {x86_64,i686}-fedora13-linux-gnu. Few longer opcodes with nasm on
{x86_64,i686}-fedora13-linux-gnu have been checked as safe.
Change-Id: I0b2ec6f01afb061d92841887affb5ca0084f936f