pm2fb: Permedia 2V initialization fixes

This patch:
- initializes correctly the Permedia2V chip if it is not initialized by BIOS
- puts back clock frequency for the ELSA WINNER board to 100kHz
- fixes returned error values from setcolreg() function
- uses more general classes for PCI ids

Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>