zig 0.15 compat fixes (#19)

Author: FalsePattern

build.zig

@@ -16,20 +16,25 @@ pub fn build(b: *std.Build) void {
 
  const tests = b.addTest(.{
  .name = "zopengl-tests",
- .root_source_file = b.path("src/zopengl.zig"),
- .target = target,
- .optimize = optimize,
+ .root_module = b.createModule(.{
+ .root_source_file = b.path("src/zopengl.zig"),
+ .target = target,
+ .optimize = optimize,
+ }),
  });
  b.installArtifact(tests);
 
  test_step.dependOn(&b.addRunArtifact(tests).step);
  }
 
- const lib = b.addStaticLibrary(.{
+ const lib = b.addLibrary(.{
  .name = "zopengl",
- .root_source_file = b.path("src/zopengl.zig"),
- .target = target,
- .optimize = optimize,
+ .linkage = .static,
+ .root_module = b.createModule(.{
+ .root_source_file = b.path("src/zopengl.zig"),
+ .target = target,
+ .optimize = optimize,
+ }),
  });
  _ = b.installArtifact(lib);
 }