ARM: u8500_defconfig: remove staging from defconfig

Ux500 was enabling the staging drivers due to the RMI4
touchscreen driver, this is now properly upstream, so drop
this and the dead symbol for the old RMI4 hack from
the defconfig.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

arch/arm/configs/u8500_defconfig

@@ -104,8 +104,6 @@ CONFIG_RTC_DRV_AB8500=y
 CONFIG_RTC_DRV_PL031=y
 CONFIG_DMADEVICES=y
 CONFIG_STE_DMA40=y
-CONFIG_STAGING=y
-CONFIG_TOUCHSCREEN_SYNAPTICS_I2C_RMI4=y
 CONFIG_HSEM_U8500=y
 CONFIG_IIO=y
 CONFIG_IIO_ST_ACCEL_3AXIS=y