msm8974-common: Commonize simpler version of mkbootimg

Change-Id: Idf4458e15060ed29283e2aaa2c1c14afb31223df
Revert "msm8974: Upgrade ACDB files"

 * Will revisit, causes issues for new project.

This reverts commit 4499de3870fdae2d1bca28442eb3c5aafee7eadd.

Change-Id: Ia3d0bbe915921d5793ca71d79fe45151e3f9c2d2