i2c: designware: Group all DesignWare drivers under a single option

There are quite a few drivers and options for the DesignWare
I2C adapter in the Kconfig. Grouping all of them under the
I2C_DESIGNWARE_CORE. That makes the menuconfig a bit more
easier to understand.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>

drivers/i2c/busses/Kconfig

@@ -559,28 +559,33 @@ config I2C_DAVINCI
 	  For details please see http://www.ti.com/davinci
 
 config I2C_DESIGNWARE_CORE
-	tristate
+	tristate "Synopsys DesignWare I2C adapter"
 	select REGMAP
+	help
+	  This option enables support for the Synopsys DesignWare I2C adapter.
+	  This driver includes support for the I2C host on the Synopsys
+	  Designware I2C adapter.
+
+	  To compile the driver as a module, choose M here: the module will be
+	  called i2c-designware-core.
+
+if I2C_DESIGNWARE_CORE
 
 config I2C_DESIGNWARE_SLAVE
 	bool "Synopsys DesignWare Slave"
-	depends on I2C_DESIGNWARE_CORE
 	select I2C_SLAVE
 	help
 	  If you say yes to this option, support will be included for the
 	  Synopsys DesignWare I2C slave adapter.
 
-	  This is not a standalone module, this module compiles together with
-	  i2c-designware-core.
-
 config I2C_DESIGNWARE_PLATFORM
-	tristate "Synopsys DesignWare Platform"
+	tristate "Synopsys DesignWare Platform driver"
 	depends on (ACPI && COMMON_CLK) || !ACPI
-	select I2C_DESIGNWARE_CORE
 	select MFD_SYSCON if MIPS_BAIKAL_T1
+	default I2C_DESIGNWARE_CORE
 	help
 	  If you say yes to this option, support will be included for the
-	  Synopsys DesignWare I2C adapter.
+	  Synopsys DesignWare I2C adapters on the platform bus.
 
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-designware-platform.
@@ -613,17 +618,19 @@ config I2C_DESIGNWARE_BAYTRAIL
 	  a BayTrail system using the AXP288.
 
 config I2C_DESIGNWARE_PCI
-	tristate "Synopsys DesignWare PCI"
+	tristate "Synopsys DesignWare PCI driver"
 	depends on PCI
-	select I2C_DESIGNWARE_CORE
 	select I2C_CCGX_UCSI
 	help
 	  If you say yes to this option, support will be included for the
-	  Synopsys DesignWare I2C adapter. Only master mode is supported.
+	  Synopsys DesignWare I2C adapters on the PCI bus. Only master mode is
+	  supported.
 
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-designware-pci.
 
+endif
+
 config I2C_DIGICOLOR
 	tristate "Conexant Digicolor I2C driver"
 	depends on ARCH_DIGICOLOR || COMPILE_TEST