This reverts commit 79af7fbf4ef0185fa501e23a900a2ad933f845a7.
Because:
* btashton reported some issues in local builds:
https://github.com/apache/incubator-nuttx/pull/603#issuecomment-602264860
* this might be related to the current CI breakage:
> /bin/sh: 1: /__w/incubator-nuttx/incubator-nuttx/nuttx/tools/mkdeps: not found
In the two pass build, the application logic is built during the first phase, pass 1. In that phase, the application may generate and install source files in the pass1/directory. The operating system is built during phase 2 of the build. At that time, those source files in the pass1/ directory will be built and incorporated into the kernel address space.
The primary purpose of the pass1/ directory is to such application-generated kernel symbol tables. For an example of the use of this feature, look at apps/examples/module/drivers/Makefile. Kernel symbol tables are needed to support kernel modules. Of course, addition board-specific logic in, say, configs/<board>/src would have to be included to make use of the application-installed symbol tables.