net: aquantia: Make some functions static

Fixes the following sparse warnings:

drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_utils.c:525:5: warning:
 symbol 'hw_atl_utils_mpi_set_speed' was not declared. Should it be static?
drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_utils.c:536:5: warning:
 symbol 'hw_atl_utils_mpi_set_state' was not declared. Should it be static?
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_utils.c

@@ -522,7 +522,7 @@ void hw_atl_utils_mpi_read_stats(struct aq_hw_s *self,
 err_exit:;
 }
 
-int hw_atl_utils_mpi_set_speed(struct aq_hw_s *self, u32 speed)
+static int hw_atl_utils_mpi_set_speed(struct aq_hw_s *self, u32 speed)
 {
 	u32 val = aq_hw_read_reg(self, HW_ATL_MPI_CONTROL_ADR);
 
@@ -533,7 +533,7 @@ int hw_atl_utils_mpi_set_speed(struct aq_hw_s *self, u32 speed)
 	return 0;
 }
 
-int hw_atl_utils_mpi_set_state(struct aq_hw_s *self,
+static int hw_atl_utils_mpi_set_state(struct aq_hw_s *self,
 				      enum hal_atl_utils_fw_state_e state)
 {
 	int err = 0;