ARM: omap1: move lcd_dma code into omapfb driver

The omapfb driver is split into platform specific code for omap1, and
driver code that is also specific to omap1.

Moving both parts into the driver directory simplifies the structure
and avoids the dependency on certain omap machine header files.

As mach/lcd_dma.h can not be included from include/linux/omap-dma.h
any more now, move the omap_lcd_dma_running() declaration into the
omap-dma header, which matches where it is defined.

Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>