devres: add debug command to dump device resources

This new command can dump all device resources associated to
each device.  The fields in every line shows:
  - The address of the resource
  - The size of the resource
  - The name of the release function
  - The stage in which the resource has been acquired (BIND/PROBE)

Currently, there is no driver using devres, but if such drivers are
implemented, the output of this command should look like this:

=> dm devres
- root_driver
- soc
- extbus
- serial@54006800
    bfb541e8 (8 byte) devm_kmalloc_release  BIND
    bfb54440 (4 byte) devm_kmalloc_release  PROBE
    bfb54460 (4 byte) devm_kmalloc_release  PROBE
- serial@54006900
    bfb54270 (8 byte) devm_kmalloc_release  BIND
- gpio@55000000
- i2c@58780000
    bfb5bce8 (12 byte) devm_kmalloc_release  PROBE
    bfb5bd10 (4 byte) devm_kmalloc_release  PROBE
- eeprom
    bfb54418 (12 byte) devm_kmalloc_release  BIND

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/core/Kconfig b/drivers/core/Kconfig
index 8ae0072..c82b564 100644
--- a/drivers/core/Kconfig
+++ b/drivers/core/Kconfig
@@ -93,10 +93,11 @@
 	  devm_kmalloc() to kmalloc(), etc.
 
 config DEBUG_DEVRES
-	bool "Managed device resources verbose debug messages"
+	bool "Managed device resources debugging functions"
 	depends on DEVRES
 	help
 	  If this option is enabled, devres debug messages are printed.
+	  Also, a function is available to dump a list of device resources.
 	  Select this if you are having a problem with devres or want to
 	  debug resource management for a managed device.