i2c: eg20t: Fix Kconfig dependencies

The i2c-eg20t driver is for a companion chip to the Intel Atom E600
series processors. These are 32-bit x86 processors so the driver is
only needed on X86_32. Add COMPILE_TEST as an alternative, so that the
driver can still be build-tested elsewhere.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

drivers/i2c/busses/Kconfig

@@ -449,7 +449,7 @@ config I2C_EFM32
 
 config I2C_EG20T
 	tristate "Intel EG20T PCH/LAPIS Semicon IOH(ML7213/ML7223/ML7831) I2C"
-	depends on PCI
+	depends on PCI && (X86_32 || COMPILE_TEST)
 	help
 	  This driver is for PCH(Platform controller Hub) I2C of EG20T which
 	  is an IOH(Input/Output Hub) for x86 embedded processor.