wrong merging of kernel "optional" setting

[teto]

Describe the bug

The optional character of a kernel configuration is set to true upon merging instead of false.

The fix is to update kernel_config.nix to:

  mergeFalseByDefault = locs: defs:
    if defs == [] then abort "This case should never happen."
    else if any (x: x.value == false) defs then false
    else true;

I need to update/check the tests too

Maintainer information:

# a list of nixpkgs attributes affected by the problem
attribute:
# a list of nixos modules affected by the problem
module:

[teto]

Also fixing this or some other fixes I have makes kernel compilation fail
because the config asks for a module but ends up with a yes (the value for
INET_TCP_DIAG is not requested thus it gets set to the default of INET_DIAG,
which is 'y').

config INET_TCP_DIAG
	depends on INET_DIAG
	def_tristate INET_DIAG

[stale]

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[teto]

fixed in staging