drm/amd/display: remove redundant initialization of variable remainder

Variable remainder is being initialized with a value that is never read,
the assignment is redundant and can be removed. Also add a newline
after the declaration to clean up the coding style.

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