pseries: Minor cleanups to HPT management hypercalls
* Standardize on 'ptex' instead of 'pte_index' for HPTE index variables
for consistency and brevity
* Avoid variables named 'index'; shadowing index(3) from libc can lead to
surprising bugs if the variable is removed, because compiler errors
might not appear for remaining references
* Clarify index calculations in h_enter() - we have two cases, H_EXACT
where the exact HPTE slot is given, and !H_EXACT where we search for
an empty slot within the hash bucket. Make the calculation more
consistent between the cases.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>