i2c: xlr: rename ARCH_TANGOX to ARCH_TANGO

The ARCH name was changed during the review process of the mach, and
this driver was forgotten to be converted. Fix it now.
http://article.gmane.org/gmane.linux.ports.arm.kernel/456331

Signed-off-by: Marc Gonzalez <marc_gonzalez@sigmadesigns.com>
[wsa: updated commit message slightly]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

drivers/i2c/busses/Kconfig

@@ -965,7 +965,7 @@ config I2C_XILINX
 
 config I2C_XLR
 	tristate "Netlogic XLR and Sigma Designs I2C support"
-	depends on CPU_XLR || ARCH_TANGOX
+	depends on CPU_XLR || ARCH_TANGO
 	help
 	  This driver enables support for the on-chip I2C interface of
 	  the Netlogic XLR/XLS MIPS processors and Sigma Designs SOCs.