[MIPS] Alchemy: kill useless #include's, #define's and extern's

Go thru the Alchemy code and hunt down every unneeded #include, #define, and
extern (some of which refer to already long dead functions).

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/au1000/common/dma.c b/arch/mips/au1000/common/dma.c
index c78260d..95f69ea 100644
--- a/arch/mips/au1000/common/dma.c
+++ b/arch/mips/au1000/common/dma.c
@@ -33,12 +33,9 @@
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>
-#include <linux/sched.h>
 #include <linux/spinlock.h>
-#include <linux/string.h>
-#include <linux/delay.h>
 #include <linux/interrupt.h>
-#include <asm/system.h>
+
 #include <asm/mach-au1x00/au1000.h>
 #include <asm/mach-au1x00/au1000_dma.h>