x86: Clean ups and fixes after bitops changes.

x86: Clean ups and fixes after bitops changes.

Firstly, the vlapic bitops need fewer casts.

Secondly, the minimum-alignment check is unnecessary and also breaks
the build (page_info's type_info field has alignment == 1). It is an
unnecessary check because bitops operate on only one bit of the word
they access, so lack of atomicity of the read and writeback does not
matter -- furthermore the LOCKed variants are guaranteed atomic
regardless of alignment.

Signed-off-by: Keir Fraser <keir.fraser@citrix.com>