staging: wfx: fix naming of hif_tx_rate_retry_policy

In the wfx driver, the prefix 'hif_mib_' is normally used for structures
that represent a hardware message. hif_mib_tx_rate_retry_policy does not
fall in this category. So, rename it.

Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20200907101521.66082-28-Jerome.Pouiller@silabs.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>