Refactor qmk_install.sh (#10681)

util/install/arch.sh

@@ -0,0 +1,16 @@
+#!/bin/bash
+
+_qmk_install() {
+    echo "Installing dependencies"
+
+    sudo pacman --needed  --noconfirm -S \
+        base-devel clang diffutils gcc git unzip wget zip \
+        python-pip \
+        avr-binutils \
+        arm-none-eabi-binutils arm-none-eabi-gcc arm-none-eabi-newlib \
+        avrdude dfu-programmer dfu-util
+    sudo pacman --needed --noconfirm -U https://archive.archlinux.org/packages/a/avr-gcc/avr-gcc-8.3.0-1-x86_64.pkg.tar.xz
+    sudo pacman --needed --noconfirm -S avr-libc # Must be installed after the above, or it will bring in the latest avr-gcc instead
+
+    python3 -m pip install --user -r $QMK_FIRMWARE_DIR/requirements.txt
+}