[ARM] 5209/1: metronomefb: changes to use platform framebuffer

These changes are used in order to support the use of the framebuffer
provided by the platform device driver rather than to directly allocate one.
Other changes are cleanup to error handling and order of release.

Signed-off-by: Jaya Kumar <jayakumar.lkml@gmail.com>
Acked-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Acked-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>