RIL subclasses: Fix processSolicited for the new API

Obviously based on the work by rmcc: https://github.com/CyanogenMod/android_frameworks_opt_telephony/commit/603113fa8177fa29a2f42982dffd0e48e8b4d9ba

It needs to un-comment the lines in BoardConfig.mk and in system.prop.
Then, please, revert: https://github.com/P880-dev/android_device_lge_p880/commit/9532b2b400752831736362077a1af19b26f1849d