powerpc/32s: Remove unused counters incremented by create_hpte()

primary_pteg_full and htab_hash_searches are not used.

Remove them.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/6470ab99e58c84a5445af43ce4d1d772b0dc3e93.1606247495.git.christophe.leroy@csgroup.eu