'kconfig edit' broken when cross compiling is not needed

This was caused by the changes in !2023 (merged).

When the target arch == native arch, it tries to install things that make no sense:

(429248) [19:43:09] (native) calculate depends of ccache-cross-symlinks, gcc-x86_64, g++-x86_64 (pmbootstrap -v for details)
(429248) [19:43:09] ERROR: Could not find dependency 'gcc-x86_64' in any aports folder or APKINDEX. See <https://postmarketos.org/depends>

I applied the following patch to pmb/build/init.py, which works around the above error:

diff --git a/pmb/build/init.py b/pmb/build/init.py
index 480352875..4bc4cecd3 100644
--- a/pmb/build/init.py
+++ b/pmb/build/init.py
@@ -86,8 +86,10 @@ def init_compiler(args, depends, cross, arch):
         cross_pkgs += ["gcc4-" + arch]
     elif "gcc6" in depends:
         cross_pkgs += ["gcc6-" + arch]
-    else:
+    elif arch != args.arch_native:
         cross_pkgs += ["gcc-" + arch, "g++-" + arch]
+    else:
+        cross_pkgs += ["gcc", "g++"]
     if "clang" in depends or "clang-dev" in depends:
         cross_pkgs += ["clang"]
     if cross == "crossdirect":

However there's another failure later from menuconfig:

scripts/kconfig/mconf  Kconfig
scripts/Kconfig.include:36: linker 'x86_64-alpine-linux-musl-ld' not found
make[1]: *** [scripts/kconfig/Makefile:33: menuconfig] Error 1
make: *** [Makefile:590: menuconfig] Error 2

I haven't had time to look into it any further than that. @z3ntu fyi