selftests: drivers: hw: ethtool.sh: Adjust output

Some log_test calls are done in a loop, and lead to the same log output.
This might prove tricky to deduplicate for automated tools. Instead, roll
the unique information from log_info to log_test, and drop the log_info.
This also leads to more compact and clearer output.

This change prompts rewording the messages so that they are not excessively
long.

Some check_err messages do not indicate what the issue actually is, so
reword them to say it's a "ping with", like is the case in some other
instances in this test.

Signed-off-by: Petr Machata <[e-mail]>
Signed-off-by: Paolo Abeni <[e-mail]>

tools/testing/selftests/drivers/net/hw/ethtool.sh

···
 		setup_wait_dev_with_timeout $h1
 		setup_wait_dev_with_timeout $h2
 		ping_do $h1 192.0.2.2
-		check_err $? "speed $speed autoneg off"
-		log_test "force of same speed autoneg off"
-		log_info "speed = $speed"
+		check_err $? "ping with speed $speed autoneg off"
+		log_test "force speed $speed on both ends"
 	done
 
 	ethtool -s $h2 autoneg on
···
 		setup_wait_dev_with_timeout $h1
 		setup_wait_dev_with_timeout $h2
 		ping_do $h1 192.0.2.2
-		check_err $? "h1-speed=$speed autoneg off, h2 autoneg on"
-		log_test "one side with autoneg off and another with autoneg on"
-		log_info "force speed = $speed"
+		check_err $? "ping with h1-speed=$speed autoneg off, h2 autoneg on"
+		log_test "force speed $speed vs. autoneg"
 	done
 
 	ethtool -s $h1 autoneg on
···
 		setup_wait_dev_with_timeout $h1
 		setup_wait_dev_with_timeout $h2
 		ping_do $h1 192.0.2.2
-		check_err $? "h1=$speed_1_to_advertise, h2=$speed_2_to_advertise ($speed_value)"
+		check_err $? "ping with h1=$speed_1_to_advertise, h2=$speed_2_to_advertise ($speed_value)"
 
-		log_test "advertise subset of speeds"
-		log_info "h1=$speed_1_to_advertise, h2=$speed_2_to_advertise"
+		log_test "advertise $speed_1_to_advertise vs. $speed_2_to_advertise"
 	done
 
 	ethtool -s $h2 autoneg on