Avoid 'static __inline' on HPUX

Avoid 'static __inline' on HPUX

'static __inline' functions on HPUX can segfault the /opt/ansic compiler
(unless we lose debugging symbols). So, just use 'static' for those
functions on HPUX. Also revert a9368a6c3dfe4435ec2ae63fff4a3325104ed9f7,
so we get a static inline function on other platforms.

Reviewed-on: http://gerrit.openafs.org/691
Tested-by: Andrew Deason <adeason@sinenomine.net>
Reviewed-by: Derrick Brashear <shadow@dementia.org>