[POWERPC] PS3: Frame buffer system-bus rework

Convert the ps3fb device from a platform device to a PS3 system bus device.
Fix the remove and shutdown methods to support kexec and to make ps3fb a
loadable module.

Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 403dac7..9b7a76b 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -1790,8 +1790,8 @@
 	  adaptor, found on some IBM System P (pSeries) machines.
 
 config FB_PS3
-	bool "PS3 GPU framebuffer driver"
-	depends on (FB = y) && PS3_PS3AV
+	tristate "PS3 GPU framebuffer driver"
+	depends on FB && PS3_PS3AV
 	select FB_SYS_FILLRECT
 	select FB_SYS_COPYAREA
 	select FB_SYS_IMAGEBLIT