build: embed udev rules in the binary

It is nice if the program can emit its own udev file.

build.zig

@@ -22,6 +22,12 @@ pub fn build(b: *std.Build) void {
         .{ .target = target, .optimize = optimize, .use_udev = use_udev },
     );
     exe.linkLibrary(ljacklm_dep.artifact("ljacklm"));
+    exe.root_module.addImport(
+        "udev_rules",
+        b.addModule("udev_rules", .{
+            .root_source_file = b.path("deps/labjack/exodriver/udev_rules.zig"),
+        }),
+    );
 
     b.installArtifact(exe);
 }

deps/labjack/exodriver/udev_rules.zig

@@ -0,0 +1,2 @@
+pub const rules_filename = "90-labjack.rules";
+pub const rules = @embedFile(rules_filename);

src/main.zig

@@ -4,6 +4,8 @@ const Config = @import("./Config.zig");
 const lj = @import("./labjack.zig");
 const RotCtl = @import("./RotCtl.zig");
 
+const udev = @import("udev_rules");
+
 const log = std.log.scoped(.main);
 
 pub fn main() !u8 {