I re-read the modified code, and it has defines in place
for building on Windows; I was defining ACCESSPERMS
universally, but it should only be defined for non-Windows
systems, which the context in this code means Linux/BSD.

Signed-off-by: Leah Rowe <leah@libreboot.org>

musl libc is very conservative in what it implements,
preferring a very "pure" libc implementation. this means
that it lacks many of the niceties found in others like
the GNU C Library; the latter implements many BSD libc
extensions, for example.

ACCESSPERMS is a #define in BSD libc that does:
S_IRWXU | S_IRWXG | S_IRWXO

Essentially, it provides a bitwise OR providing chmod 0777,
which can be used as shorthand in calls to functions such
as mkdir() available in all libc implementations.

In the case of uefitool, this define is indeed used on mkdir.
Conditionally re-define ACCESSPERMS, if undefined, so that musl
libc can be used when building uefitool.

Signed-off-by: Leah Rowe <leah@libreboot.org>

don't hardcode the check based on whether the current
project is grub. instead, define "btype" in target.cfg

if unset, we assume kconfig and permit kconfig commands
e.g. make menuconfig, make silentoldconfig, etc

this is to avoid the deadliest of sins:
project-specific hacks

Signed-off-by: Leah Rowe <leah@libreboot.org>

it is no longer hardcoded just to be handled for uefiextract.

it is now defined as cmakedir in target.cfg, for a single or
multi tree project. if multi tree, it is applied to the specific
tree, and has to be defined per tree

the way it works is: as per cmakelist, a project will define
which directory is to be built, and it will then generate
a makefile in the main source tree (the build tree in cmake
language, where the main CMakeLists.txt file exists)

when the makefile has been generated, the project is then treated
like any other project. the way cmake works, if a makefile has
already been generated by it, in a given directory, running it
again will fail and not affect anything; if it fails but the
makefile doesn't exist, then something is wrong, but if the
makefile does exist, then it's all fine and nothing happens

at present, this is only used for uefiextract, which is part
of src/uefitool

Signed-off-by: Leah Rowe <leah@libreboot.org>