Staging: hv: remove PAGE_SIZE and PAGE_SHIFT and __builtin functions

The kernel provides all of this, and actually gets it correct, so don't
try to redefine these types of things.

Cc: Hank Janssen <hjanssen@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>