ice: make fwlog functions static

ice: make fwlog functions static

ice_fwlog_supported(), ice_fwlog_get() and ice_fwlog_supported() aren't
called outside the ice_fwlog.c file. Make it static and move in the file
to allow clean build.

Drop ice_fwlog_get(). It is called only from ice_fwlog_init() function
where the fwlog support is already checked. There is no need to check it
again, call ice_aq_fwlog_get() instead.

Drop no longer valid comment from ice_fwlog_get_supported().

Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Signed-off-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>