nvim: Add support for clangd for C++ and ccls for C

clangd doesn't work the way I want it to with C.
ccls doesn't work the way I want it to with C++.

So now I use both for each ones they work well with.

dotfiles/nvim/lua/plugins/lsp/c.lua

@@ -1,5 +1,8 @@
 return function ()
-  require"lspconfig".clangd.setup {
-    capabilities = require"cmp_nvim_lsp".default_capabilities()
+  require"lspconfig".ccls.setup {
+    capabilities = require"cmp_nvim_lsp".default_capabilities(),
+    filetypes = {
+      "c"
+    }
   }
 end