[TC] pmagb-b-fb: Convert to the driver model

This is a set of changes to convert the driver to the driver model.  As a
side-effect the driver now supports building as a module.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: James Simmons <jsimmons@infradead.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 18c22ba..45fe65d 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -1454,8 +1454,8 @@
 	  used mainly in the MIPS-based DECstation series.
 
 config FB_PMAGB_B
-	bool "PMAGB-B TURBOchannel framebuffer support"
-	depends on (FB = y) && TC
+	tristate "PMAGB-B TURBOchannel framebuffer support"
+	depends on TC
  	select FB_CFB_FILLRECT
  	select FB_CFB_COPYAREA
  	select FB_CFB_IMAGEBLIT