Increase the allocator order and fix a bug on the headers installed

When a kernel for a davinci board is built, increase the order of the
allocator to 13, i.e 2^12 max contiguous chunk size (16MB). Looks like it is
harmless. Also add the davincifb.h header file when the kernel headers are
installed.

arch/arm/Kconfig

@@ -508,8 +508,9 @@ source "arch/arm/common/Kconfig"
 
 config FORCE_MAX_ZONEORDER
 	int
-	depends on SA1111
-	default "9"
+	depends on SA1111 || ARCH_DAVINCI
+	default "9" if SA1111
+	default "13" if ARCH_DAVINCI
 
 menu "Bus support"
 

include/video/Kbuild

-unifdef-y += sisfb.h
+unifdef-y += sisfb.h davincifb.h