Move lsp config to local file structure

.config/nvim/lsp/tblgen_lsp_server.lua

@@ -0,0 +1,28 @@
+---@brief
+---
+--- https://mlir.llvm.org/docs/Tools/MLIRLSP/#tablegen-lsp-language-server--tblgen-lsp-server
+---
+--- The Language Server for the LLVM TableGen language
+---
+--- `tblgen-lsp-server` can be installed at the llvm-project repository (https://github.com/llvm/llvm-project)
+
+local function get_command()
+  local cmd = { 'tblgen-lsp-server' }
+  local files = vim.fs.find(
+    { 'tablegen_compile_commands.yml', 'build/tablegen_compile_commands.yml' },
+    { path = vim.fn.expand('%:p:h'), upward = true, type = 'file' }
+  )
+  if #files > 0 then
+    local file = files[1]
+    table.insert(cmd, '--tablegen-compilation-database=' .. file)
+  end
+
+  return cmd
+end
+
+---@type vim.lsp.Config
+return {
+  cmd = get_command(),
+  filetypes = { 'tablegen' },
+  root_markers = { 'tablegen_compile_commands.yml', '.git' },
+}