soc: qcom: geni: Fix unused label warning

soc: qcom: geni: Fix unused label warning

If CONFIG_SERIAL_EARLYCON is not set, gcc warns this:

drivers/soc/qcom/qcom-geni-se.c: In function 'geni_se_probe'
drivers/soc/qcom/qcom-geni-se.c:914:1: warning: label 'exit' defined but not used [-Wunused-label]
 exit:
 ^~~~

Fixes: b622b16743f1 ("soc: qcom-geni-se: Add interconnect support to fix earlycon crash")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20200722020619.25988-1-yuehaibing@huawei.com
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>