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

Change-Id: I4af7f34919ae1e94b960fcabfcfb70fe50825cf7
Merge branch 'cm-11.0' of
github.com:CyanogenMod/android_kernel_htc_msm8960 into cm-11.0