fix up implementation of int get_partition_device
fix up implementation of int get_partition_device

Change-Id: I142b15228322790892dd07b10d6a3f31440badc7

InsomniaAOSP/platform_bootable_recovery,DerTeufel/dualboot_recovery,DerTeufel/dualboot_recovery,kylinmoddev/android_bootable_recovery,randomblame/bootable_recovery,76Demented/bootable_recovery-,Plain-Andy/android_platform_bootable_recovery,randomblame/bootable_recovery,InsomniaAOSP/platform_bootable_recovery,randomblame/bootable_recovery,InsomniaAOSP/platform_bootable_recovery,DerTeufel/dualboot_recovery,Plain-Andy/android_platform_bootable_recovery,InsomniaAOSP/platform_bootable_recovery,76Demented/bootable_recovery-,randomblame/bootable_recovery,kylinmoddev/android_bootable_recovery,Plain-Andy/android_platform_bootable_recovery,kylinmoddev/android_bootable_recovery,InsomniaAOSP/platform_bootable_recovery,kylinmoddev/android_bootable_recovery,randomblame/bootable_recovery,76Demented/bootable_recovery-,Plain-Andy/android_platform_bootable_recovery,76Demented/bootable_recovery-,DerTeufel/dualboot_recovery,76Demented/bootable_recovery-,DerTeufel/dualboot_recovery