Gentoo: Add kconfig patch from genpatches and set default config for …

…the new Gentoo-specific entries

I'm not sure about enabling GENTOO_LINUX_INIT_SYSTEMD by default, so Gentoo users please give feedback :)

Should satisfy #1006

linux-tkg-config/prepare

@@ -765,6 +765,12 @@ _tkg_srcprep() {
     _msg="Import Suse-specific patches" && _tkg_patcher
   fi
 
+  if [ "$_distro" = "Gentoo" ]; then
+    # https://dev.gentoo.org/~mpagano/genpatches/trunk/
+    tkgpatch="$srcdir/0013-gentoo-kconfig.patch"
+    _msg="Import Gentoo-kconfig patches" && _tkg_patcher
+  fi
+
   if [ -z $_misc_adds ]; then
     plain "Enable misc additions ? They may contain temporary fixes pending upstream, or some other changes that can break on non-Arch distros."
     read -rp "`echo $'    > [Y]/n : '`" _interactive_misc_adds;
@@ -1019,6 +1025,12 @@ _tkg_srcprep() {
     fi
   fi
 
+  if [ "$_distro" = "Gentoo" ]; then
+    # Default config for Gentoo as defined in kconfig
+    _enable "GENTOO_LINUX" "GENTOO_LINUX_UDEV" "GENTOO_LINUX_PORTAGE" "GENTOO_LINUX_INIT_SCRIPT" "GENTOO_PRINT_FIRMWARE_INFO"
+    _disable "GENTOO_LINUX_INIT_SYSTEMD" "GENTOO_KERNEL_SELF_PROTECTION" # Should we enable systemd support?
+  fi
+
   # Prevent Debian and Ubuntu to sign stuff because it breaks stuff
   if [[ "$_distro" = "Debian" || "$_distro" = "Ubuntu" ]]; then
     #Help Debian cert compile problem.