don't complain if recovery icon is short
don't complain if recovery icon is short

If the a recovery icon file is so short that we can't even read the
8-byte header, put a message in the log but not on the device screen.
We intentionally have zero-length files for some icons on some devices,
if they're never shown (eg, the firmware installation icons are only
used on HTC devices).

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