dma-mapping: move debug configuration options to kernel/dma

This is a follow up to the commit cf65a0f6f6ff

("dma-mapping: move all DMA mapping code to kernel/dma")

which moved source code of DMA API to kernel/dma folder. Since there is
no file left in the lib that require DMA API debugging options move the
latter to kernel/dma as well.

Cc: Christoph Hellwig <[e-mail]>
Signed-off-by: Andy Shevchenko <[e-mail]>
Signed-off-by: Christoph Hellwig <[e-mail]>

kernel/dma/Kconfig

···
 config DMA_DIRECT_REMAP
 	bool
 	select DMA_REMAP
+
+config DMA_API_DEBUG
+	bool "Enable debugging of DMA-API usage"
+	select NEED_DMA_MAP_STATE
+	help
+	  Enable this option to debug the use of the DMA API by device drivers.
+	  With this option you will be able to detect common bugs in device
+	  drivers like double-freeing of DMA mappings or freeing mappings that
+	  were never allocated.
+
+	  This also attempts to catch cases where a page owned by DMA is
+	  accessed by the cpu in a way that could cause data corruption.  For
+	  example, this enables cow_user_page() to check that the source page is
+	  not undergoing DMA.
+
+	  This option causes a performance degradation.  Use only if you want to
+	  debug device drivers and dma interactions.
+
+	  If unsure, say N.
+
+config DMA_API_DEBUG_SG
+	bool "Debug DMA scatter-gather usage"
+	default y
+	depends on DMA_API_DEBUG
+	help
+	  Perform extra checking that callers of dma_map_sg() have respected the
+	  appropriate segment length/boundary limits for the given device when
+	  preparing DMA scatterlists.
+
+	  This is particularly likely to have been overlooked in cases where the
+	  dma_map_sg() API is used for general bulk mapping of pages rather than
+	  preparing literal scatter-gather descriptors, where there is a risk of
+	  unexpected behaviour from DMA API implementations if the scatterlist
+	  is technically out-of-spec.
+
+	  If unsure, say N.

lib/Kconfig.debug

···
 
 	  See Documentation/debugging-via-ohci1394.txt for more information.
 
-config DMA_API_DEBUG
-	bool "Enable debugging of DMA-API usage"
-	select NEED_DMA_MAP_STATE
-	help
-	  Enable this option to debug the use of the DMA API by device drivers.
-	  With this option you will be able to detect common bugs in device
-	  drivers like double-freeing of DMA mappings or freeing mappings that
-	  were never allocated.
-
-	  This also attempts to catch cases where a page owned by DMA is
-	  accessed by the cpu in a way that could cause data corruption.  For
-	  example, this enables cow_user_page() to check that the source page is
-	  not undergoing DMA.
-
-	  This option causes a performance degradation.  Use only if you want to
-	  debug device drivers and dma interactions.
-
-	  If unsure, say N.
-
-config DMA_API_DEBUG_SG
-	bool "Debug DMA scatter-gather usage"
-	default y
-	depends on DMA_API_DEBUG
-	help
-	  Perform extra checking that callers of dma_map_sg() have respected the
-	  appropriate segment length/boundary limits for the given device when
-	  preparing DMA scatterlists.
-
-	  This is particularly likely to have been overlooked in cases where the
-	  dma_map_sg() API is used for general bulk mapping of pages rather than
-	  preparing literal scatter-gather descriptors, where there is a risk of
-	  unexpected behaviour from DMA API implementations if the scatterlist
-	  is technically out-of-spec.
-
-	  If unsure, say N.
-
 menuconfig RUNTIME_TESTING_MENU
 	bool "Runtime Testing"
 	def_bool y