mips,unicore32: swiotlb doesn't need sg->dma_length

Only mips and unicore32 select CONFIG_NEED_SG_DMA_LENGTH when building
swiotlb.  swiotlb itself never merges segements and doesn't accesses the
dma_length field directly, so drop the dependency.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: James Hogan <jhogan@kernel.org>
diff --git a/arch/mips/cavium-octeon/Kconfig b/arch/mips/cavium-octeon/Kconfig
index 5d73041..eb5faee 100644
--- a/arch/mips/cavium-octeon/Kconfig
+++ b/arch/mips/cavium-octeon/Kconfig
@@ -70,7 +70,6 @@
 config SWIOTLB
 	def_bool y
 	select DMA_DIRECT_OPS
-	select NEED_SG_DMA_LENGTH
 
 config OCTEON_ILM
 	tristate "Module to measure interrupt latency using Octeon CIU Timer"
diff --git a/arch/mips/loongson64/Kconfig b/arch/mips/loongson64/Kconfig
index 641a147..2a4fb91 100644
--- a/arch/mips/loongson64/Kconfig
+++ b/arch/mips/loongson64/Kconfig
@@ -135,7 +135,6 @@
 	default y
 	depends on CPU_LOONGSON3
 	select DMA_DIRECT_OPS
-	select NEED_SG_DMA_LENGTH
 	select NEED_DMA_MAP_STATE
 
 config PHYS48_TO_HT40
diff --git a/arch/unicore32/mm/Kconfig b/arch/unicore32/mm/Kconfig
index 1d9fed0..45b7f76 100644
--- a/arch/unicore32/mm/Kconfig
+++ b/arch/unicore32/mm/Kconfig
@@ -43,4 +43,3 @@
 config SWIOTLB
 	def_bool y
 	select DMA_DIRECT_OPS
-	select NEED_SG_DMA_LENGTH