patch cmake to implement a NIXPKGS_CMAKE_PREFIX_PATH env variable which
is similar to CMAKE_PREFIX_PATH except it is not searched for programs.
This is required because cmake will search CMAKE_PREFIX_PATH for
programs before PATH which is problematic as that means buildInputs gets
searched before nativeBuildInputs which can break things when the
binaries in PATH are covered or the order re-arranged.
This commit adds the -type f filter to the find command. Previously, -type f
only applied to the first file name: *.cmake. The -o command means that -type f
has to be added back for the other file names.
