drm/radeon: fix typo in fetching mpll params
drm/radeon: fix typo in fetching mpll params

Copy-paste typo.  Value should be 0-2, not 0-1.

Noticed-by: Sylvain BERTRAND <7f6f9744a366798b19668a1e9de91b7de794e08f@legeek.net>
Signed-off-by: Alex Deucher <08dc22c6156113f2deff178e35e3ed9b24d6af9e@amd.com>
Cc: 4fbacc2fa0ffdbb11bf1ad6925b886ebd08dd15f@vger.kernel.org

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs