drm/amd/pm: fix spelling mistake in various messages "power_dpm_force_perfomance_level"

There are spelling mistakes in error and warning messages, the text
power_dpm_force_perfomance_level is missing a letter r and should be
power_dpm_force_performance_level.  Fix them.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>