refactor(os): Simplify mkinitcpio.conf manipulation (#6)

setup.sh

@@ -497,11 +497,8 @@ function in_file_in_array_remove_n () {
 function add_zfs_hook_to_initramfs () {
     #1.16
     # Add zfs hook, remove fsck hook from initramfs.
-    sed -ri \
-        -e 's'$'\x1''(HOOKS=)(.*?[( ])(filesystems)([) ][^\r\n\f]*)'$'\x1''\1\2zfs \3\4'$'\x1''g' \
-        -e 's'$'\x1''((\()(fsck)(\)))'$'\x1''\2\4'$'\x1''g' \
-        -e 's'$'\x1''(([[:space:]]+)(fsck)|(fsck)([[:space:]]+))'$'\x1'''$'\x1''g' \
-        '/mnt/etc/mkinitcpio.conf'
+    in_file_in_array_insert_n_before_m '/mnt/etc/mkinitcpio.conf' 'HOOKS' 'zfs' 'filesystems'
+    in_file_in_array_remove_n '/mnt/etc/mkinitcpio.conf' 'HOOKS' 'fsck'
     # Also unless encryption's unwanted add plain text key file into
     # initramfs since it's living inside an encrypted pool anyway.
     [[ ! "${ARCHZBM_ZFSPROPS_NO_ENCRYPTION}" ]] && sed -ri \