Support for show partition names in block device vfs.

Based on commit eb53446318d1cbed5de8bb30285ba995d34f4927

    Author: Flemmard <flemmard@gmail.com>
    Date:   Mon Apr 21 20:25:10 2014 +0200

    block: support volname for HTC devices with proc/emmc support

    gets data from emmc_partitions and write it down on mmcblk0pX partitions
    this enables vold by-name mappings
Merge commit 'f3f17c12fb2584d5038025dc8503f1d88271e8cc' into jelly_3.4