[RFC] Add namespacing to configs and includes to fix conflicts

[Krishna Chaitanya]

Hi,

We have a hostap fork in ZephyrRTOS project
https://github.com/zephyrproject-rtos/hostap.
In the past and recently too, we have found conflicts in CONFIG
options and includes, so,
I would like to check the community's stance on the proposed solutions
below before we implement the below proposed solutions.

Both are invasive (though a bit easier to implement), and may not
directly offer benefits to
Linux implementation, but other forks might benefit from this.

Problem 1: Using CONFIG_ macros without any namespace can cause conflicts
with existing macros or Kconfig options.

Solution 1: Use HOSTAP namespace for all config, e.g.,  `CONFIG_WNM`
-> `CONFIG_HOSTAP_WNM`.

Problem 2: Using includes with filenames directly and using generic
names like "common.h"
and "includes.h" can cause conflicts with existing headers.

Solution2: Use full paths, e.g., `common.h` -> `hostap/src/utils/common.h`

WDYT?