drm/mgag200: fix typo causing bw limits to be ignored on some chips
drm/mgag200: fix typo causing bw limits to be ignored on some chips

mode->mdev otherwise the bw limits never kick in.

Reported in RHEL testing.

Cc: 4fbacc2fa0ffdbb11bf1ad6925b886ebd08dd15f@vger.kernel.org
Signed-off-by: Dave Airlie <f2295d84e358395675bc8031be58672073ae065e@redhat.com>

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