Kernel is always defined

Kernel is always defined

When we build the kernel module, either in the real or the ukernel
case, KERNEL is defined. So, remove the #ifdefs around our locking
primitives, so that things are a little bit clearer.

Change-Id: I60893cc630d8cd4dd6cb11cdc44e8bf4f2f9f863
Reviewed-on: http://gerrit.openafs.org/838
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: Derrick Brashear <shadow@dementia.org>