Total number of pkeys calculation is off by 1. Fix it.
Fixes: 4fb158f65ac5 ("powerpc: track allocation status of all pkeys")
Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
         * arch-neutral code.
         */
        pkeys_total = min_t(int, pkeys_total,
-                       (ARCH_VM_PKEY_FLAGS >> VM_PKEY_SHIFT));
+                       ((ARCH_VM_PKEY_FLAGS >> VM_PKEY_SHIFT)+1));
 
        if (!pkey_mmu_enabled() || radix_enabled() || !pkeys_total)
                static_branch_enable(&pkey_disabled);