[ARM] 5034/1: fix arm{925,926,940,946} dma_flush_range() in WT mode

The CPU's dma_flush_range() operation needs to clean+invalidate the
given memory area if the cache is in writeback mode, or do just the
invalidate part if the cache is in writethrough mode, but the current
proc-arm{925,926,940,946} (incorrectly) do a cache clean in the
latter case.  This patch fixes that.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mm/proc-arm940.S b/arch/arm/mm/proc-arm940.S
index 44ead90..1a3d63d 100644
--- a/arch/arm/mm/proc-arm940.S
+++ b/arch/arm/mm/proc-arm940.S
@@ -222,7 +222,7 @@
 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
 	mcr	p15, 0, r3, c7, c14, 2		@ clean/flush D entry
 #else
-	mcr	p15, 0, r3, c7, c10, 2		@ clean D entry
+	mcr	p15, 0, r3, c7, c6, 2		@ invalidate D entry
 #endif
 	subs	r3, r3, #1 << 26
 	bcs	2b				@ entries 63 to 0