nixos: make several kernel common-config options optional

Realistically, common-config is useful, but there are a lot of things in
there that are non-optionally specified that aren't always useful. For
example, when deploying grsecurity, I don't want the bluetooth,
wireless, or input joystick/extra filesystem stack (XFS, etc), nor the
staging drivers tree.

The problem is that if you specify this in your own kernel config in the
grsecurity module, by saying 'BT n' to turn off bluetooth,
common-config turns on 'BT_HCIUART_BCSP y', which then becomes unused
and errors out.

This is really just an arbitrary picking at the moment, but it should be
OK.

Signed-off-by: Austin Seipp <aseipp@pobox.com>
nixos: Fix sysctl option merging

Using pkgs.lib.mkOverride in a sysctl option would throw a bogus error.

Also, if you defined a sysctl multiple times in the same configuration,
only one of the values would be picked up, while the others were silently
discarded.

This patch should fix both issues. If you define a sysctl multiple
times at your highest defined priority level, you will get a proper
error with detailed location information.
glibc_multi: fix ldd on x86_64
glibc_multi: fix typo
keyutils: Update from 1.5.8 -> 1.5.9
ecryptfs: Update from 82 -> 104
grsecurity: Add paxctl, paxmark and stdenv.needsPax to stdenv
spl: Fix compilation with grsecurity's constify plugin and kernels < 3.8
qimageblitz: Mark stack as non-executable (patch taken from Gentoo)

This allows applications such as okular and kolourpaint to run in
grsecurity kernels, which disallow executable stacks by default.
firefox: Add support for grsecurity
polkit: Add support for grsecurity
llvm: Add support for grsecurity
gcc: Add support for grsecurity
oraclejdk7: Add support for grsecurity
spidermonkey: Add support for grsecurity
gstreamer: Add support for grsecurity
grub: Add support for grsecurity
mesa-noglu: Add support for grsecurity
ghc: Add support for grsecurity

In this case, we also need to specify compilation flags to mark stacks as
non-executable, otherwise PaX will not allow ghc or binaries built by ghc
to run.  This is what gentoo-hardened does as well.
openjdkBootstrap: Add support for grsecurity