ARM: pxa: magician: Optimize powerup delays for Samsung LCD

Delays for the Samsung LCD are greater than needed. These values were
extracted from a datasheet.

Signed-off-by: Petr Cvek <petr.cvek@tul.cz>
Acked-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>