ARM: sirf: use CONFIG_SIRF rather than CONFIG_PRIMA2 where necessary

I got a build error today that made me realize that it is not
possible to build a kernel for a SiRF platform without enabling
CONFIG_PRIMA2, since a lot of common code depends on CONFIG_PRIMA2.

This fixes all occurences that appear like common SiRF code.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Mark Brown <broonie@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Barry Song <Baohua.Song@csr.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 631736e..73e2e7d 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -685,7 +685,7 @@
 
 config I2C_SIRF
 	tristate "CSR SiRFprimaII I2C interface"
-	depends on ARCH_PRIMA2
+	depends on ARCH_SIRF
 	help
 	  If you say yes to this option, support will be included for the
 	  CSR SiRFprimaII I2C interface.