[nxp][imx] Fix structual issues with nxp/imx

Add proper targets for imx7d based boards
Add proper targets for imx6ul based boards
Add default values for MEMBASE, MEMSIZE and KERNEL_SIZE
Add selected debug uart to gloabl defines

Change-Id: I1464e1e3a5050509fa7737c918c6254447bb1c39
7 files changed
tree: 33d2bffda0b23a90c025c808cfcfbd14148ffe84
  1. app/
  2. platform/
  3. target/