pepper: cm.dependencies use default branch

Change-Id: I48b661926a5ecdcd2ba6a6a954da7184ee964c4e
pepper: remove duplicate configs

Change-Id: I8b2a125a6877f81d061ef2584f44bbf3b13be1b6
pepper: rename cm_defconfig

Change-Id: I6bf40fcf9a098bab68512333ef93c0b1bc016fb2