Remove img-functions from ramdisk-image-create.

Ramdisk-image-create sources both img-functions and ramdisk-functions
causing duplicate functions. To correct this situation this patch
removes the import of img-functions from ramdisk-image-create.
It moves cleanup_dirs and run_d functions from img-functions to
common-functions to allow this.

fixes bug 1175427
Authored-by: Chris Krelle <nobodycam@gmail.com>

Change-Id: I971d019b0d92b06d9de661663b49c433e823ea42
Merge "Remove img-functions from ramdisk-image-create."