x86 floppy: kill off the 'register' keyword from header

When compilers became generally better at optimizing code than humans, the
register keyword became mostly useless. For the floppy driver it certainly
is since it's so slow compared to the rest of the system that optimizing
access to a single variable or two isn't going to make any real difference
So let's just leave it to the compiler - it'll do a better job anyway.

This patch does away with a few register keywords in the x86 floppy driver.

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>