drm/amd/pm: Simplify managed I2C transfer functions

drm/amd/pm: Simplify managed I2C transfer functions

Now that we have an I2C quirk table for
SMU-managed I2C controllers, the I2C core does the
checks for us, so we don't need to do them, and so
simplify the managed I2C transfer functions.

Also, for Arcturus and Navi10, fix setting the
command type from "cmd->CmdConfig" to "cmd->Cmd".
The latter is what appears to be taking in
the enumeration I2C_CMD_... as an integer,
not a bit-flag.

For Sienna, the "Cmd" field seems to have been
eliminated, and command type and flags all live in
the "CmdConfig" field--this is left untouched.

Fix: Detect and add changing of direction
bit-flag, as this is necessary for the SMU to
detect the direction change in the 1-d array of
data it gets.

Cc: Jean Delvare <jdelvare@suse.de>
Cc: Alexander Deucher <Alexander.Deucher@amd.com>
Cc: Andrey Grodzovsky <Andrey.Grodzovsky@amd.com>
Cc: Lijo Lazar <Lijo.Lazar@amd.com>
Cc: Stanley Yang <Stanley.Yang@amd.com>
Cc: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Luben Tuikov <luben.tuikov@amd.com>
Acked-by: Alexander Deucher <Alexander.Deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>