Video/Framebuffer: add fuctional power management support to Blackfin BF54x LQ043 framebuffer driver

Fix bug: does nor properply resume after suspend mem
Fix for PM_SUSPEND_MEM: Save and restore peripheral base and DMA registers
Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NBryan Wu <cooloney@kernel.org>
Acked-by: NKrzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>