arch-packages: Update package list

In neovim, we run this after saving a file. However, when opening a
Haskell file which is outside of a project or in a directory which
has all other Haskell code, it would generate tags for every project
in this directory blocking neovim in the mean time.

arch-packages/pkglist.txt

@@ -154,6 +154,7 @@ hadolint-bin
 haveged
 hdparm
 helix
+helvum
 hexyl
 hotdoc
 htop
@@ -196,6 +197,7 @@ linux-atm
 linux-firmware
 linux-headers
 linux-zen
+linux-zen-headers
 lldb
 llvm
 logrotate
@@ -384,6 +386,7 @@ unzip
 upower
 usb_modeswitch
 usbutils
+v4l2loopback-dkms
 vale-bin
 valgrind
 vimiv-qt

fish/.config/fish/functions/fasttags.fish

@@ -1,7 +1,9 @@
 function fasttags --description "Generate tags for Haskell project"
-    if not test -e tags
-        fast-tags --fully-qualified -R .
-    else
-        fast-tags --fully-qualified -R $argv
+    if test -d .git
+        if not test -e tags
+            fast-tags --fully-qualified -R .
+        else
+            fast-tags --fully-qualified -R $argv
+        end
     end
 end