IPA version 4.9 and later use a different layout of some fields
found in the COMP_CFG register.

Define arbitration_lock_disable_encoded(), and use it to encode a
value into the ATOMIC_FETCHER_ARB_LOCK_DIS field based on the IPA
version.

And define full_flush_rsc_closure_en_encoded() to encode a value
into the FULL_FLUSH_WAIT_RSC_CLOSE_EN field based on the IPA
version.

The values of these fields are neither modified nor extracted by
current code, but this patch makes this possible for all supported
versions.

Fix a mistaken comment above ipa_hardware_config_comp() intended to
describe the purpose for the register.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>