mpc8308: Migrate system io config to Kconfig

Migrate the system IO configuration setting to Kconfig.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
diff --git a/configs/mpc8308_p1m_defconfig b/configs/mpc8308_p1m_defconfig
index b0da1c0..26601ff 100644
--- a/configs/mpc8308_p1m_defconfig
+++ b/configs/mpc8308_p1m_defconfig
@@ -60,6 +60,14 @@
 CONFIG_HID0_FINAL_DPM=y
 CONFIG_HID0_FINAL_ICE=y
 CONFIG_HID2_HBE=y
+CONFIG_SICR_ESDHC_A_GPIO=y
+CONFIG_SICR_ESDHC_B_GPIO=y
+CONFIG_SICR_ESDHC_C_GTM=y
+CONFIG_SICR_GPIO_A_TSEC2=y
+CONFIG_SICR_GPIO_B_TSEC2=y
+CONFIG_SICR_IEEE1588_A_GPIO=y
+CONFIG_SICR_GTM_GPIO=y
+CONFIG_SICR_GPIOSEL_IEEE1588=y
 CONFIG_OF_BOARD_SETUP=y
 CONFIG_OF_STDOUT_VIA_ALIAS=y
 CONFIG_BOOTDELAY=5