drm/panel:simple: Fix pixclock edge and dimensions
Fix panel settings 'DRIVE_NEGEDGE' to 'SAMPLE_NEGEDGE' for 5 inch admatec DPI display. With the wrong setting 'DRIVE_NEGEDGE' 'fb-test' tool showed some flickering on thin lines.
With the change to 'SAMPLE_NEGEDGE' the flickering has gone.
Also the dimensions for this 5 inch display is fixed
Fixes issues
Edited by Eberhard Stoll